The husband of Nazanin Zaghari-Ratcliffe, the British-Iranian mother held in jail in Iran, is seeking an urgent meeting with Boris Johnson to ask what plans the government has to keep dual national prisoners safe.

Richard Ratcliffe spoke to his wife by phone on Saturday following the US drone strike that killed the Iranian general Qassem Suleimani on Thursday at Baghdad’s airport.

His wife, a 40-year-old charity worker serving five years in Tehran’s notorious Evin prison on charges of spying, was “scared and panicking”, he said. The couple had no idea what to expect, he added, but feared it could mean her serving her full term, or even another added sentence.

“Her first concerns were what is going to happen to the American prisoners. Then what will happen to us. Prior to Christmas we had our parole rejected, so it wasn’t looking good. She said to me she didn’t expect to get out before the end of her sentence, and was worried they were going to add another sentence, which they have been threatening,” said Ratcliffe, who lives in the UK where he was recently joined by their young daughter.

“We are one of their major chess pieces. Increased tensions and anger and a real volatility now will not be good news for any of those who are held,” he added.

As many as five people with dual British-Iranian nationality, or with UK connections, are believed to be in Iranian prisons. They include Kylie Moore-Gilbert, a Cambridge-educated British-Australian academic, who has been in Evin prison for more than a year, having reportedly been given a 10-year sentence.

Anoosheh Ashoori, 65, an engineer and a UK-Iran dual citizen, is serving 10 years in the same Tehran jail on spying charges. His wife, Sherry Izadi, spoke to him on Saturday and said she feared he no longer had a “hope in hell” of being released.

Ratcliffe said he was pleased the UK foreign secretary, Dominic Raab, mentioned dual nationals, and his wife, on the BBC’s Andrew Marr Show on Sunday.

“It is really important that it is made clear publicly, but also privately to President Trump and the American administration, that protecting the innocent prisoners, the hostages, who are held has to be front and centre of all their considerations,” he said.

“President Trump has done a pretty good job of getting Americans home recently. This is going to make it a lot harder.”

It was important the UK government “counsels calm”. “But also pieties aren’t going to cut it at this point. It [the government] needs to be very clear [about] its priorities for protecting British citizens. And that does need Boris Johnson to stand up and say something,” he added.

The prime minister meeting the families of those held would send a clear signal “that these lives matter” and “where his priorities are”, he added.

“We sent two naval vessels, so we are signalling that shipping is important. But we also need to be signalling in a very clear way that people held prisoner are important.”

Ratcliffe said he would be asking for Johnson “to be talking directly to President Trump about how he is keeping people safe”.

“I want to be asking Boris Johnson what is his plan. I want Boris Johnson to be asking Donald Trump what is his plan,” he said.

