In this recent but undated image released by the British Royal Marines, marines from 539 Assault Squadron Royal Marines conduct operations on waterways in the Basra region of southern Iraq as part of Operation Troy. [AP]

LONDON - Britain's military said Wednesday that British boarding vessels were 1.7 nautical miles inside Iraqi territorial waters when a Royal Navy crew was captured by
Iran.

Related readings:  Blair warns Iran standoff could escalate  Iran: Sailors being treated humanely  Blair hopes diplomacy gets sailors back  Iran: Brit sailors may face charges  Blair calls capture of sailors 'serious'  Iran: British sailors admitted aggression  Iran seizes 15 British sailors

Meanwhile British Prime Minister Tony Blair said it is time to increase pressure on Iran following capture of navy crew.

Vice Admiral Charles Style told reporters that the Iranians had provided a position on Sunday - a location that he said was in Iraqi waters.

By Tuesday, Iranian officials had given a revised position 2 miles east, placing the British inside Iranian waters - a claim he said was not verified by GPS coordinates.

"It is hard to understand a legit reason for this change of coordinates," Style said.

Britain and the United States have said the sailors and marines were intercepted Friday after they completed a search of a civilian vessel in the Iraqi part of the Shatt al-Arab waterway, where the border between Iran and Iraq has been disputed for centuries.

Iran has said that the 15 British sailors and marines were being treated well, but refused to say where they were being held, or rule out the possibility that they could be brought to trial for allegedly entering Iranian waters.

Iranian Foreign Ministry spokesman Mohammad Ali Hosseini said the case was following normal procedures, holding out the possibility that the Britons could be brought to trial.

He said the Britons were being treated well and that the only woman among the sailors, 26-year-old Faye Turney, had been given privacy.

"They are in completely good health. Rest assured that they have been treated with humanitarian and moral behavior," Hosseini told The Associated Press.

In talks with Iranian Foreign Minister Manouchehr Mottaki, British Foreign Secretary Margaret Beckett demanded that British diplomats be allowed to meet with the crew to make their own assessment.