The Iranian ambassador to London on Saturday urged Britain to help Iran mend relations with the international community after Iran "showed our goodwill" by freeing 15 captured British sailors and marines. The British crew, who said they had been subject to psychological pressure and coercion in captivity, began two-weeks' leave with their families as The Financial Times newspaper published an interview with Iranian Ambassador Rasoul Movahedian. "Now it is up to the British government to proceed in a positive way," he was quoted as saying. "We will welcome in general any steps that could defuse tensions in the region," he added. The British mariners, captured in the Persian Gulf on March 23, were freed Wednesday by Iranian President Mahmoud Ahmadinejad, who called their release a gift to Britain. Movahedian called on Britain to use the resolution of the crisis as a chance to "establish sensible lines of communication with Iran." He said the key issue for Iran was recognition from the West of its right to a nuclear power program. "That's the prime issue for Iran and I think that could help set a new basis for our future relations with Western countries," he said. The United States and allies, including Britain, fear Iran is pursuing a nuclear weapons program under cover of its civilian nuclear program. Iran denies this, insisting it seeks to use the program only for nuclear energy. The newspaper said Movahedian spoke before several crew members said on Friday that they had been blindfolded, bound, kept in solitary confinement and subjected to psychological pressure during their captivity. They said they were coerced into saying they had been in Iranian waters when they were detained. Marine Danny Masterton, of Muirkirk, Scotland, said Saturday he had feared he would be killed in Iranian custody and his body dragged through the streets of Teheran. The sailor said the mariners were frequently interrogated and kept in dirty prison cells. On one occasion guards cocked weapons and lined the crew against a wall. "It was the most terrifying moment of my life. I thought my time had come and just waited for the bang," Masterton said, speaking about the ordeal for the first time in an interview with Scotland's Sunday Mail newspaper, editions of which were available late Saturday. "All I could think about was my family, and all I could hope was that they would send my dead body home and not drag it through the streets or bury it in a hole in the ground somewhere." Britain's Observer newspaper claimed Saturday that interrogators had told the crew they had become interested in their activities after an interview with one of the sailors was broadcast on British television on March 13 - 10 days before their capture. In the footage, Cpt. Chris Air - one of the 15 later seized - told Britain's Channel 5 how the sailors were working to interrupt terrorism and piracy in the Persian Gulf. Iran dismissed Friday's news conference as propaganda - just as Britain had condemned the crew members' frequent appearances on Iranian TV during their captivity. Britain's Foreign Office had no immediate comment on the ambassador's remarks. A spokesman said officials "will need to time to assess the implication for diplomatic relations with Iran" of the crew's accounts of their treatment. Teheran says the crew was in Iranian waters in the Shatt al-Arab waterway, a long-disputed dividing line between Iraq and Iran. Britain insists its troops were in Iraqi waters working under a UN mandate. Prime Minister Tony Blair has insisted Britain did not negotiate for the sailors' release, and did not offer an apology for their alleged trespass into Iranian waters. On Saturday, the Vatican said Pope Benedict XVI had written to Iran's supreme leader, Ayatollah Ali Khamenei, to intercede for the release of the crew. Vatican officials declined to give details of the letter, although The Guardian newspaper reported that the letter had asked Iran to free the crew in time for Sunday's Easter holiday as a religious gesture of goodwill. Movahedian told the Financial Times that the crew's release was not connected to the fate of five Iranians held by US forces in Iraq. US officials said last week that Iran would be granted access to the detainees, but denied the decision was linked to the fate of British crew. Britain also has denied a link. But Movahedian indicated help from the British on the matter would be appreciated. "If they want to be helpful and use their influence we will welcome that. ... We will welcome in general any steps that could defuse tensions in the region." Despite the resolution of the crisis, tensions in the Persian Gulf remain high. The US has two aircraft carrier groups off Iran's coast, its largest show of force in the region since the 2003 invasion of Iraq. The Guardian newspaper reported Saturday that the US military offered to mount "aggressive patrols" over Iranian Revolutionary Guard bases after the sailors and marines were captured. The newspaper, which did not name its sources, said Britain had declined the offer and asked the US to tone down its military activity in the Gulf. The Guardian said US forces "modified their exercises to make them less confrontational." The Foreign Office declined to comment on the report.