We may see Prime Minister Blair take a more aggressive stance on this problem after all. As expected, the Brits have GPS data to verify the positions of their personnel, but are trying to settle this out of the public eye before they take it all public and, presumably, raise a really big stink.
“What we are trying to do … is to pursue this through the diplomatic channels and make the Iranian government understand these people have to be released and that there is absolutely no justification whatever for holding them,” [British PM Tony] Blair said.
“They have to release them. If not, then this will move into a different phase,” he told Britain’s GMTV television.
Blair’s spokesman said the next step London could take would be to publish proof, in the form of global satellite positioning (GPS) records, that the sailors had not entered Iranian waters.
“We so far haven’t made explicit why we know that because we don’t want to escalate this,” he said.
A government source in London told Reuters British officials were showing Iran data on the sailors’ exact position when seized.
— Paul Hughes, “Blair warns Iran of ‘different phase’“. Reuters | UK, 27 March 2007. [Emphasis mine]
Hopefully that phase involves an ultimatum and more proactive measures to secure the release of the captives. And no small punitive action against the IRGC and Iranian Navy. You’re not just seeking the release of fifteen captives, but reminding Iran that she may not trespass on another country’s territory at will, and abduct a third party’s sailors and marines because it is politically convenient.