Android Police has published that Google will soon introduce its Assistant to the iOS platform.
Google Assistant will be limited to the United State at launch and while other regions would have to water for few days or weeks.
Currently, the only root (apart from Google Search app) for iOS users to access Google Assistant was via Allo.
Availability of the Assistant functionality as part of the Search app was not clearly stated for not or may be it would be a different app on its own.
Google is expected to launch the Assistant feature very soon and it could even be this week at the Google I/O as speculated.