The communiqués have been flying back and forth and the tone has often been sharp. One of the latest rounds in the dispute over 15 British soldiers taken into Iranian custody involved a strongly worded condemnation by the European Union and a sharp response from Iran.

German Foreign Minister Frank-Walter Steinmeier, hosting EU foreign ministers in Bremen Saturday, called for the immediate release of the sailors and expressed the bloc's solidarity over the issue.

"We are standing shoulder to shoulder with the United Kingdom," he told reporters.

Tehran countered with a warning for the EU to stay out of it.

"The European Union foreign ministers must seriously avoid irresponsible and imprudent reactions over the bilateral dispute between Tehran and London," read a statement released by Iranian foreign ministry officials.

Ali Larijani, head of Iran's supreme national security council, said Monday that the European Union had "started to condemn Iran without knowing the facts" over the sailors' capture.

He criticized the EU's expression last week of "unconditional support" for Britain's position and its threat of "appropriate measures" unless the captives were released quickly, in an interview with Britain's Channel Four news.

But behind the posturing in this latest diplomatic clash with Iran, some foreign-policy experts say there are real consequences for the nation regarding a resolution of its disputed nuclear program. Some western nations, particularly the United States, believe the program is a covert effort to build atomic bombs despite Tehran's denials.

"The European Union's stance on Iran has evolved to become more skeptical as Iran loses more and more credibility," said Tomas Valasek, director of foreign policy and defense at the Centre for European Reform, a London-based think tank.

"This situation isn't doing Iran any good regarding negotiations," he said. "Iran is bleeding its goodwill."

Unbending

After the seven British sailors and eight Royal Marines were captured in the Shatt al Arab waterway on March 23, the British began quiet diplomacy for their release. But once they pushed it onto the international stage, experts say that Iran felt compelled to up the ante.

This weekend, Iranian television showed some of the soldiers confessing to entering Iranian territory and apologizing -- although it is unclear whether or not those statements were coerced. Earlier on Monday, an Iranian state-run television station said all 15 British sailors and marines had confessed to illegally entering Iranian waters.

Britain maintains its personnel were in Iraqi territory on smuggling patrols under a UN mandate. The maritime border has never been officially recognized, experts say.

Also, over the weekend, Iranian President Mahmoud Ahmadinejad said that there would be further developments regarding its nuclear program soon.

Some say Iran grabbed the soldiers because of its nervousness over an UN resolution to force their hand on the nuclear issue. The Security Council widened sanctions against Iran last week after it defied a second deadline for it to stop enriching uranium, which Iran says will only yield electricity

"Taking the soldiers just before a Security Council resolution is a clear sign by the Iranians to show they can do something, too," said Johannes Reissner, a Middle East expert at the German Institute for International and Security Affairs in Berlin.

"They want to send a signal that they will not bend," he said.

Other motives

Some observers believe that Iranian actions have more to do with seizures of Iranians in Iraq. Five Iranian officials have been held by US forces in Iraq since January. The US says that computers and other equipment seized during the raid provided information on Iranian involvement in attacks on US forces in Iraq.

"It is clearly tit-for-tat," said Valasek. "The Iranians were clearly up to no good in Iraq and their people were captured. Iran wants them back and also wants to discourage further incidents as well."

Some experts also believe that this is the latest in Iran's strategy to force Britain out of Iraq, leaving the US without its staunchest ally.

"It is clearly an Iranian aim to isolate the US," one EU official told DPA. "The question now is, where do we go from here?"

Harsh Pant, an international security expert in the defense studies department at King's College in London believes that Iran is trying to test how far the west is willing to go in stopping its nuclear program and its regional ambitions.

"The west has few cards to play because there isn't a unified position on economic sanctions or a threat of military action," he said. "So it has few options when diplomacy fails – unless it takes a strong, unified position."

Quiet diplomacy

But since the recent sharp words between London and Tehran, there has been some movement towards a possible way out of the standoff.

"Things have gone a little quieter and we hope that this is a good sign," Foreign Secretary Margaret Beckett told reporters in Bremen. "What we want is a way out of this, we want it peacefully and we want it as soon as possible."

On Monday, both Iran and Britain signalled possible ways out of the standoff over the naval personnel. Tehran promised to stop airing video confessions and Britain said it was willing to discuss ways to avoid future boundary confusion in the Persian Gulf.

While a British official told the AP news service that Britain still wants the captives freed unconditionally, Iranian state-run radio said the confessions by the naval personnel would not be broadcast because of what it called "positive changes" in Britain's negotiating stance. The radio did not elaborate on the changes.

The EU has also asked chief diplomat Javier Solana to make contact with the Iranians and Middle East expert Reisser says that quiet diplomacy is the best course of action for the Europeans.

"Freezing diplomatic relations would not be wise," he said. "It is important to watch developments closely and use quiet channels to keep things from blowing up."