He says his mission now is to help other dual nationals, still detained in Iranian prison.
Among those still there is Morad Tabhaz from Hammersmith, who was released briefly but reimprisoned, and has since gone on hunger strike.
He arrived home - alongside fellow British-Iranian Nazanin Zaghari-Ratcliffe last week - after spending five years in prison for spying which he denied.
The retired engineer says he isn't sure whether he'll accept the Prime Minister's invitation - suggesting there may be a "bit of opportunism involved in it".