friends_withdraw_friendship( int $initiator_userid, int $friend_userid )

function friends_withdraw_friendship( $initiator_userid, $friend_userid ) {
	$friendship_id = BP_Friends_Friendship::get_friendship_id( $initiator_userid, $friend_userid );
	$friendship    = new BP_Friends_Friendship( $friendship_id, true, false );

	if ( empty( $friendship->is_confirmed ) && BP_Friends_Friendship::withdraw( $friendship_id ) ) {

		// @deprecated Since 1.9
		do_action_ref_array( 'friends_friendship_whithdrawn', array( $friendship_id, &$friendship ) );

		/**
		 * Fires after a connection request has been withdrawn.
		 *
		 * @since BuddyPress 1.9.0
		 *
		 * @param int                   $friendship_id ID of the friendship.
		 * @param BP_Friends_Friendship $friendship    Friendship object. Passed by reference.
		 */
		do_action_ref_array( 'friends_friendship_withdrawn',  array( $friendship_id, &$friendship ) );

		return true;
	}

	return false;
}