diff --git a/keyserver/src/endpoints.js b/keyserver/src/endpoints.js
--- a/keyserver/src/endpoints.js
+++ b/keyserver/src/endpoints.js
@@ -18,7 +18,10 @@
   calendarQueryUpdateResponder,
 } from './responders/entry-responders.js';
 import type { JSONResponder } from './responders/handlers.js';
-import { getSessionPublicKeysResponder } from './responders/keys-responders.js';
+import {
+  getSessionPublicKeysResponder,
+  getOlmSessionInitializationDataResponder,
+} from './responders/keys-responders.js';
 import {
   createOrUpdatePublicLinkResponder,
   disableInviteLinkResponder,
@@ -303,6 +306,10 @@
     responder: uploadMediaMetadataResponder,
     requiredPolicies: baseLegalPolicies,
   },
+  get_olm_session_initialization_data: {
+    responder: getOlmSessionInitializationDataResponder,
+    requiredPolicies: [],
+  },
 };
 
 export { jsonEndpoints };
diff --git a/keyserver/src/responders/keys-responders.js b/keyserver/src/responders/keys-responders.js
--- a/keyserver/src/responders/keys-responders.js
+++ b/keyserver/src/responders/keys-responders.js
@@ -1,18 +1,32 @@
 // @flow
 
+import type { Account as OlmAccount } from '@commapp/olm';
 import t, { type TUnion } from 'tcomb';
 
-import type { GetSessionPublicKeysArgs } from 'lib/types/request-types.js';
+import type {
+  OlmSessionInitializationInfo,
+  GetOlmSessionInitializationDataResponse,
+  GetSessionPublicKeysArgs,
+} from 'lib/types/request-types.js';
 import {
   type SessionPublicKeys,
   sessionPublicKeysValidator,
 } from 'lib/types/session-types.js';
+import { ServerError } from 'lib/utils/errors.js';
 import { tShape, tNull } from 'lib/utils/validation-utils.js';
 
 import { fetchSessionPublicKeys } from '../fetchers/key-fetchers.js';
+import { verifyClientSupported } from '../session/version.js';
 import type { Viewer } from '../session/viewer.js';
+import { fetchCallUpdateOlmAccount } from '../updaters/olm-account-updater.js';
+import { validateAccountPrekey } from '../utils/olm-utils.js';
 import { validateInput, validateOutput } from '../utils/validation-utils.js';
 
+type AccountKeysSet = {
+  +identityKeys: string,
+  ...OlmSessionInitializationInfo,
+};
+
 const getSessionPublicKeysInputValidator = tShape<GetSessionPublicKeysArgs>({
   session: t.String,
 });
@@ -41,4 +55,95 @@
   );
 }
 
-export { getSessionPublicKeysResponder };
+async function retrieveAccountKeysSet(
+  account: OlmAccount,
+): Promise<AccountKeysSet> {
+  const identityKeys = account.identity_keys();
+
+  await validateAccountPrekey(account);
+  const prekey = account.prekey();
+  // Until transfer of prekeys to the identity service is implemented
+  // prekeys will be marked as published each time it is accessed
+  // to establish olm notifs session to mitigate the risk of prekeys
+  // being in use for long enough to cause security concerns
+  account.mark_prekey_as_published();
+  const prekeySignature = account.prekey_signature();
+
+  if (!prekeySignature) {
+    throw new ServerError('prekey_validation_failure');
+  }
+
+  account.generate_one_time_keys(1);
+  const oneTimeKey = account.one_time_keys();
+  account.mark_keys_as_published();
+
+  return { identityKeys, oneTimeKey, prekey, prekeySignature };
+}
+
+async function getOlmSessionInitializationDataResponder(
+  viewer: Viewer,
+): Promise<GetOlmSessionInitializationDataResponse> {
+  await verifyClientSupported(viewer);
+
+  const {
+    identityKeys: notificationsIdentityKeys,
+    prekey: notificationsPrekey,
+    prekeySignature: notificationsPrekeySignature,
+    oneTimeKey: notificationsOneTimeKey,
+  } = await fetchCallUpdateOlmAccount('notifications', retrieveAccountKeysSet);
+
+  const contentAccountCallback = async (account: OlmAccount) => {
+    const {
+      identityKeys: contentIdentityKeys,
+      oneTimeKey,
+      prekey,
+      prekeySignature,
+    } = await retrieveAccountKeysSet(account);
+
+    const identityKeysBlob = {
+      primaryIdentityPublicKeys: JSON.parse(contentIdentityKeys),
+      notificationIdentityPublicKeys: JSON.parse(notificationsIdentityKeys),
+    };
+    const identityKeysBlobPayload = JSON.stringify(identityKeysBlob);
+    const signedIdentityKeysBlob = {
+      payload: identityKeysBlobPayload,
+      signature: account.sign(identityKeysBlobPayload),
+    };
+
+    return {
+      signedIdentityKeysBlob,
+      oneTimeKey,
+      prekey,
+      prekeySignature,
+    };
+  };
+
+  const {
+    signedIdentityKeysBlob,
+    prekey: contentPrekey,
+    prekeySignature: contentPrekeySignature,
+    oneTimeKey: contentOneTimeKey,
+  } = await fetchCallUpdateOlmAccount('content', contentAccountCallback);
+
+  const notifInitializationInfo = {
+    prekey: notificationsPrekey,
+    prekeySignature: notificationsPrekeySignature,
+    oneTimeKey: notificationsOneTimeKey,
+  };
+  const contentInitializationInfo = {
+    prekey: contentPrekey,
+    prekeySignature: contentPrekeySignature,
+    oneTimeKey: contentOneTimeKey,
+  };
+
+  return {
+    signedIdentityKeysBlob,
+    contentInitializationInfo,
+    notifInitializationInfo,
+  };
+}
+
+export {
+  getSessionPublicKeysResponder,
+  getOlmSessionInitializationDataResponder,
+};
diff --git a/lib/actions/user-actions.js b/lib/actions/user-actions.js
--- a/lib/actions/user-actions.js
+++ b/lib/actions/user-actions.js
@@ -14,7 +14,10 @@
   UpdateUserAvatarRequest,
   UpdateUserAvatarResponse,
 } from '../types/avatar-types.js';
-import type { GetSessionPublicKeysArgs } from '../types/request-types.js';
+import type {
+  GetSessionPublicKeysArgs,
+  GetOlmSessionInitializationDataResponse,
+} from '../types/request-types.js';
 import type {
   UserSearchResult,
   ExactUserSearchResult,
@@ -256,6 +259,20 @@
     return await callServerEndpoint('get_session_public_keys', data);
   };
 
+const getOlmSessionInitializationDataActionTypes = Object.freeze({
+  started: 'GET_OLM_SESSION_INITIALIZATION_DATA_STARTED',
+  success: 'GET_OLM_SESSION_INITIALIZATION_DATA_SUCCESS',
+  failed: 'GET_OLM_SESSION_INITIALIZATION_DATA_FAILED',
+});
+
+const getOlmSessionInitializationData =
+  (
+    callServerEndpoint: CallServerEndpoint,
+  ): (() => Promise<GetOlmSessionInitializationDataResponse>) =>
+  async () => {
+    return await callServerEndpoint('get_olm_session_initialization_data', {});
+  };
+
 const policyAcknowledgmentActionTypes = Object.freeze({
   started: 'POLICY_ACKNOWLEDGMENT_STARTED',
   success: 'POLICY_ACKNOWLEDGMENT_SUCCESS',
@@ -294,6 +311,8 @@
   deleteAccount,
   deleteAccountActionTypes,
   getSessionPublicKeys,
+  getOlmSessionInitializationDataActionTypes,
+  getOlmSessionInitializationData,
   mergeUserInfos,
   logIn,
   logInActionTypes,
diff --git a/lib/types/endpoints.js b/lib/types/endpoints.js
--- a/lib/types/endpoints.js
+++ b/lib/types/endpoints.js
@@ -94,6 +94,7 @@
   UPDATE_USER_AVATAR: 'update_user_avatar',
   UPLOAD_MEDIA_METADATA: 'upload_media_metadata',
   SEARCH_MESSAGES: 'search_messages',
+  GET_OLM_SESSION_INITIALIZATION_DATA: 'get_olm_session_initialization_data',
 });
 type SocketPreferredEndpoint = $Values<typeof socketPreferredEndpoints>;
 
diff --git a/lib/types/redux-types.js b/lib/types/redux-types.js
--- a/lib/types/redux-types.js
+++ b/lib/types/redux-types.js
@@ -77,7 +77,10 @@
   QueueReportsPayload,
   ReportStore,
 } from './report-types.js';
-import type { ProcessServerRequestsPayload } from './request-types.js';
+import type {
+  ProcessServerRequestsPayload,
+  GetOlmSessionInitializationDataResponse,
+} from './request-types.js';
 import type {
   UserSearchResult,
   ExactUserSearchResult,
@@ -1115,6 +1118,22 @@
       +error: true,
       +payload: Error,
       +loadingInfo: LoadingInfo,
+    }
+  | {
+      +type: 'GET_OLM_SESSION_INITIALIZATION_DATA_STARTED',
+      +loadingInfo?: LoadingInfo,
+      +payload?: void,
+    }
+  | {
+      +type: 'GET_OLM_SESSION_INITIALIZATION_DATA_SUCCESS',
+      +payload: GetOlmSessionInitializationDataResponse,
+      +loadingInfo: LoadingInfo,
+    }
+  | {
+      +type: 'GET_OLM_SESSION_INITIALIZATION_DATA_FAILED',
+      +error: true,
+      +payload: Error,
+      +loadingInfo: LoadingInfo,
     };
 
 export type ActionPayload = ?(Object | Array<*> | $ReadOnlyArray<*> | string);
diff --git a/lib/types/request-types.js b/lib/types/request-types.js
--- a/lib/types/request-types.js
+++ b/lib/types/request-types.js
@@ -259,3 +259,15 @@
 export type GetSessionPublicKeysArgs = {
   +session: string,
 };
+
+export type OlmSessionInitializationInfo = {
+  +prekey: string,
+  +prekeySignature: string,
+  +oneTimeKey: string,
+};
+
+export type GetOlmSessionInitializationDataResponse = {
+  +signedIdentityKeysBlob: SignedIdentityKeysBlob,
+  +contentInitializationInfo: OlmSessionInitializationInfo,
+  +notifInitializationInfo: OlmSessionInitializationInfo,
+};