Iran has threatened to try 15 marines and sailors from Britain's Royal Navy for illegal entrance into Iranian waters and won't allow British diplomats to meet with the jailed servicemen.

It is still unknown precisely where the British sailors — 14 men and one woman — are being held, but Iranian officials have said they were "well and sound."

On Sunday, IranianForeign Minister Manouchehr Mottaki told reporters in New York the sailors committed an act of aggression by sailing into Iranian waters.

"The Iranian authorities intercepted these sailors and marines in Iranian waters and detained them in Iranian waters," Mottaki said. "This has happened in the past as well."

But British Prime Minister Tony Blair has argued the charge ofillegal entrance into Iranian waters isn't valid because the Royal Navy crew was actually occupying Iraqi waters at the time.

Mottaki did not specify what the consequences of the charge could be for the Royal Navy crew.

Blair characterized the detentions as "unjustified and wrong."

"It is simply not true that they went into Iranian territorial waters, and I hope the Iranian government understands how fundamental an issue this is for us," he said Sunday.

Border disputed

According to British Foreign Secretary Margaret Beckett, the sailors and marines had been working with the Baghdad government to monitor smuggling in Iraqi waters when Iran's Revolutionary Guards seized them Friday.

The U.S. and Britain have said the Royal Navy crew was in the Iraqi part of the Shaat al Arab waterway — a border that has historically been disputed between Iraq and Iran.

Media reports have raised the theory that the Revolutionary Guards may have seized the British sailors to gain leverage for the release of five of their own members, who are being held by U.S. forces in Iraq.

In a phone conversation between Beckett and Mottaki late Sunday, Mottaki gave no firm commitment on releasing the sailors.

The capture and detention of the British servicemen elevated tensions between Iran and the West. Tehran has been rejecting accusations it is interfering in the U.S.-led war against Iraq, and also faces tough sanctions for refusing to stop its nuclear program.

With files from the Associated Press