The husband of Nazanin Zaghari-Ratcliffe said he had failed to secure a breakthrough in talks with UK Prime Minister Boris Johnson about ways to secure her release after nearly four years in an Iranian jail. Richard Ratcliffe urged Mr Johnson to be “tough” in talks with Iran to secure the release of his wife, who the family say is a pawn in a broader diplomatic battle between the British government and Iran. Mr Ratcliffe went into Downing Street holding the hand of his daughter Gabriella, who had remained in Iran with her mother’s family until late last year. The meeting was his first with Mr Johnson since he became leader. "In truth, no breakthrough," said Mr Ratcliffe after Thursday’s meeting and called on the government to be “tough with Iran”. "I don't think I have come away thinking Nazanin is coming out tomorrow or even next week, and I will think carefully about what I tell her on the phone on Saturday about where the hope is to come," he said. Ms Zaghari-Ratcliffe, a British-Iranian dual national, was arrested when she travelled to see her parents with her then young daughter. She was jailed for five years and her family fear Iran will come up with ways to extend her sentence when it reaches full term. Mr Ratcliffe has previously criticised Mr Johnson when as foreign minister he told MPs that Ms Zaghari-Ratcliffe might have been in Iran to train journalists, an admission that was seized on by Iranian state media to justify her detention. Mr Johnson subsequently apologised and said that he would leave no stone unturned in trying to secure her release. Mr Ratcliffe said after the meeting that he believed that Mr Johnson was genuine in seeking her release but sympathy was not enough. Thursday’s meeting comes amid continuing wrangling in the UK’s High Court over an outstanding debt of nearly £380 million owed by Britain for an aborted arms deal that was cancelled after the 1979 revolution. Iranian leaders have hinted that the release of Ms Zaghari-Ratcliffe could be connected with payment of the debt, but UK government officials say their hands are tied by the sanctions regime. A court is holding money to pay the debt but cannot legally release it. Hamid Baeidinejad, Iran’s ambassador to the UK, on Monday claimed in a tweet that the dispute that has been subject to 30 years of legal action and arbitration was “coming to an end”. But Lawyers for Iran accepted on Wednesday that no payment could be made until the sanctions imposed in 2008 were lifted. Mr Ratcliffe this week urged the government to settle the debt with a payment in humanitarian aid to get around the sanctions regime. His local MP, Tulip Siddiq, also called on the Government to pay the sum back to Iran so that her constituent can be returned to the UK. “Anyone with a passing interest in my constituent's case will know that the debt is linked to her imprisonment,” she said. Government minister Jacob Rees-Mogg said: “The British Government cannot and must not pay or appear to pay, either in fact or reality, money to allow people who have been illegally detained to be released.”