A man has travelled to Washington to urge world leaders to help free his mother and her partner, who are imprisoned in Iran.

Lindsay and Craig Foreman, from East Sussex, were detained in January 2025 while travelling, and later sentenced to 10 years in prison in what their family called a "sham trial".

Joe Bennett told a conference at the McCain Institute on Thursday that the international community must treat their case as "a problem for the Western civilisation and the globe".

Speaking on Capitol Hill, he said: "There are days when you don't want to show up, but you have to keep going. It's heartbreaking that in this day and age this is still happening."

Bennett, from Folkestone, Kent, previously told the BBC the couple's situation had reached "a terrifying breaking point" following the outbreak of war between Iran and the US and Israel.

At the US-UK Transatlantic Conference on Hostage-Taking and Arbitrary Detention on Thursday, he criticised what he described as the UK government's "non-existent" advocacy.

He said: "They do not want to be accountable for things that go wrong, they only want to be accountable for when thing goes right.

"I know that Keir Starmer will be on the tarmac when they come home if he's still in power to shake their hand but he has never once said their name."

Bennett told the conference that proposals for a new special envoy gave him limited hope because the role "still has the shackles of the Foreign Office behind it".

He said the government's engagement with Tehran had been "very one-dimensional".

Bennett said the UK had been slow to learn of the couple's sentencing and claimed the family had been the first to tell officials after the British embassy staff left Tehran.

He says consular support offered remotely "doesn't quite" work and officials had not used the communication channels available to the family.

The government had shown "no willingness" to speak directly to his parents about efforts to secure their release, he said.

Bennett added he hoped the Washington event would strengthen cooperation between countries including the US, Germany and the UK.

The Foreign, Commonwealth and Development Office said: "The welfare of British nationals detained in Iran is a priority for this government and continues to be during the current situation in the Middle East.

"Craig and Lindsay's sentences are completely appalling and totally unjustifiable, and we will continue to pursue this case relentlessly with the Iranian regime and will do so until we see Craig and Lindsay Foreman safely returned to the UK and reunited with their family.

"We continue to provide consular assistance to them and their family."

It said that it had long advised British and British-Iranian nationals against travel to Iran due to the risk of arbitrary detention.

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