Richard Ratcliffe has called on Boris Johnson to meet him outside the Iranian embassy, where he’s been on a hunger strike for six days.
Mr Ratcliffe’s wife, British-Iranian dual national Nazanin Zaghari-Ratcliffe, has been imprisoned in Iran since April 2016.
She is on her third hunger strike since being detained, and her husband plans to join her in the protest for as long as possible.
He has called on Mr Johnson to meet at the makeshift camp on the front steps of the embassy for a “frank conversation”.
“We’ve called for him to come and that would be great and obviously I’ve said some fairly tough things about him just recently so that would be a frank conversation to have,” he told talkRADIO.
Mr Ratcliffe recently called Mr Johnson a potential threat to national security over a series of gaffes that he said led to his wife’s continued imprisonment.
He is concerned the possible future Prime Minister may not be able to “take responsibility for his mistakes”.
“I will say is I think it’s important if someone can’t take reasonability for their mistakes, they will struggle to take responsibility for the country,” he said.
“Conservative Party members will still have a vote and they’ll have a vote with their conscience, and I think it’s for them to decide who they think will best protect the citizens of this country.”
Mr Ratcliffe said he is feeling tired but “not hungry” on the sixth day of the hunger strike, and is no longer battling with the Iranian embassy.
“On Monday and Tuesday it was a bit aggressive and there were a few battles so we started bringing an extra person to sleep at night and then a third person just so there was a bit more solidity,” he said.
“It felt like there were attempts to drive us off the pavement. Things have calmed down now but it’s quite good to have a couple of people staying overnight.”