The standoff over 15 captured British sailors shows no signs of abating, and analysts say that Iran's tough stance is a demonstration of the power of hardliners unafraid to confront the West.

Events on Sunday only further polarized the situation: Two of the sailors appeared on state TV, saying they trespassed into Iranian waters, and about 200 angry Iranian youths threw rocks and firecrackers at the British Embassy and unsuccessfully tried to rush its grounds.

Iranian students from several universities shouted "Death to Britain!" and "Death to America!" and demanded the government shut down the "den of spies" — echoes of slogans from a crisis of a generation ago, when American captives were held hostage by Tehran for 444 days.

• Monitor the showdown in FOXNews.com's Iran Center.

Demonstrations in Iran must receive approval from the Interior Ministry.

The 15 Britons were detained by Iranian naval units on March 23 while patrolling for smugglers as part of a U.N.-mandated force monitoring the Persian Gulf. They were seized by Iranian naval units near the mouth of the Shatt al-Arab, a waterway that has long been a disputed dividing line between Iraq and Iran.

Iran's state-run Arabic-language TV channel said Monday that all 15 of the sailors had confessed to illegally entering Iranian waters. Britain insists the team was in Iraqi waters at the time of its capture and says the confessions appear coerced.

Iran has brushed aside diplomatic overtures from the European Union, Japan and Turkey in recent days. And hardline President Mahmoud Ahmadinejad has taken a higher-profile role, declaring in his most extensive comments on the crisis that Britain and its allies were "arrogant and selfish" for not apologizing over what he called the Britons' incursion into Iranian waters.

Before the new video was released, Britain appeared to be holding out hope for a diplomatic resolution, saying it was in direct contact with Iran and examining options for new dialogue.

Britain's Foreign Office denounced the video, saying it was "completely unacceptable for these pictures to be shown on TV."

Many observers were already pessimistic.

"This is going to be a prolonged problem," said Dr. Abdulkhaleq Abdulla, a political scientist at the United Arab Emirates University in Dubai. "There are parties in Iran who would like to turn this into another test of strong will, and to show that Iran is capable of making the West meet its demands."

It had appeared earlier in the week that the Iranians were looking for a way to end the standoff quickly. Foreign Minister Manouchehr Mottaki said Wednesday that the only woman captive, Faye Turney, would be released soon.

Within hours, however, the Iranians were rolling back on that timetable, saying that Britain's "bad behavior" had prompted them to delay her release.

Hardliners within the Iranian leadership may have overruled the release, believing that Iran needed to assert itself at a time when it feels under threat from the West, some analysts said.

"They are saying they are a power to be reckoned with in the region," said Joost Hiltermann, a Middle East expert from the International Crisis Group, a think tank. "It's a very dangerous game. Anything can go wrong at any moment."

British officials have ruled out Iran's demand that they apologize for the alleged "illegal entry" of the sailors and marines into Iranian territory. Prime Minister Tony Blair insists the seizure occurred well inside Iraqi waters.

But with the stakes high and options few, Britain has sounded willing in recent days to explore ways of seeking a dialogue with Iran — no matter how long it takes.

"The responsible way forward is to continue the often unglamorous, but important and quiet diplomatic work to get our personnel home," Transport Minister Douglas Alexander told the British Broadcasting Corp.

National pride has always been strong in Iran and hardliners have often successfully used it to rally domestic support, analysts note.

"For years, Britain has been doing whatever it could against Iran in various fields, such as the nuclear issue. They have to learn that it costs something," said Mahmoud Jafari, a 37-year-old teacher.

Public support for the government could prove a turnaround in Iran, where even conservative backers of Ahmadinejad had been criticizing him for focusing too heavily on confrontation with the West while ignoring domestic problems like high unemployment.

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