Theresa May has pressed Iranian leader Hassan Rouhani over the case of a British-Iranian woman jailed for allegedly plotting to overthrow the country's government.

Charity worker Nazanin Zaghari-Ratcliffe was jailed for five years earlier this month, and the Prime Minister used her first meeting with President Rouhani to push for progress on the case.

Mrs Zaghari-Ratcliffe, from Hampstead in northwest London, was arrested at Imam Khomeini airport on 3 April as she was flying back home to Britain after visiting family with her two-year-old daughter Gabriella.

She is being cared for by her grandparents in Tehran while Mrs Zaghari-Ratcliffe, 37, is in Evin prison.

Speaking to Sky News before the meeting, her husband Richard Ratcliffe said the situation has been frustrating.


Image: Nazanin Zaghari-Ratcliffe with her husband Richard

Asked what he wanted Mrs May to say to Mr Rouhani, he said: "Just to press personally that this is a real priority for her and for the British Government - that Iran cannot keep taking, in our case, a mother and a baby, and in other cases of British families, taking them hostage while they make a deal."

Mr Ratcliffe added: "The Government clearly does things behind the scenes I don't know about - but six months have passed that they've been held there."

The meeting between the PM and Mr Rouhani happened on the margins of the United Nations General Assembly in New York.

A UK Government source said: "When you tend to see the Prime Minister raise these types of issues with leaders, you don't expect an immediate outcome that day but hopefully you can try and unlock some momentum in the system."

Mrs May is understood to have raised concerns about the charges and the sentencing.

Image: Nazanin Zaghari-Ratcliffe with her daughter Gabriella

The source indicated future relations with Tehran could be affected by the case, saying: "We think it is important with all the relations we have with countries around the world, that we can engage frankly where there are consular issues that need resolving.

"I think our view is if we are going to have a productive relationship with Iran moving forward, if Iran wants to increase its reputation for working with international partners on things, then we should be able to raise such issues and discuss them while continuing to develop a relationship."

Last July, Iran reached a deal with Britain, along with Russia, the US, France, Germany and China which saw international sanctions on the country lifted after it agreed to curb its nuclear programme.

The deal placed restrictions of the sort of nuclear reactor it could develop, but did not require it to halt its use of nuclear energy entirely.

Mrs Zaghari-Ratcliffe was sentenced 24 hours after the UK resumed diplomatic relations with Iran.