THE Pentagon is turning to Britain once again as a site for its controversial missile defence system, The Times has learnt.

British officials have said that “discreet inquiries” are being made by American defence planners about whether the Government would accept the ten interceptor units, designed to knock out a ballistic missile fired by terrorists or states such as Iran before it reaches the US. America’s preferred option is to site the interceptors in Poland or the Czech Republic, but opposition within those countries has forced the Pentagon to look again at Britain.

The prospect will alarm Downing Street because Tony Blair has paid a heavy political price for being seen by voters as too close to George Bush over the Iraq war and unable to turn down any request from the US. One senior British source said: “A few weeks ago it looked like we were out of the woods on this one. That has changed because Central Europe no longer looks like such an easy option.”

Critics of the so-called Son of Star Wars system, a scaled-down version of the ambitious plan envisaged by Ronald Reagan in the 1980s, say that the base for the interceptor units will inevitably become a target for America’s enemies and a magnet for terrorists and the host country would receive no protection from the shield.

Britain has agreed to upgrade the Fylingdales early warning system in North Yorkshire to help the Pentagon to track incoming ballistic missiles and the US electronic surveillance base at Menwith Hill is also expected to be a key part of the system.

Lieutenant-General Trey Obering, the director of the US Missile Defence Agency, told a conference in Washington this year that the final shortlist of possible sites included Britain, Poland and the Czech Republic. John Reid, who was then the Defence Secretary, later denied that there had been any request from the US for Britain to accept the missiles and added that he did not expect the topic to be raised.

US sources said that a Central European location made more sense for intercepting missiles coming from the Middle East. They also suggested that Mr Blair’s precarious political position meant that for once the US’s most loyal ally might not be able to help.

The Pentagon said yesterday that it had no plans to place interceptors in Britain, but it is understood that inquiries have been made in Washington at a “sub-ministerial” level.

Riki Ellison, president of the Missile Defence Advocacy Alliance, a pressure group with close ties to the US Defence Department, said he knows that Britain is still in the frame “if things go wrong for us in Central Europe”. He said: “The UK has always been the fall-back option and there is some concern about whether Poland and the Czech Republic will turn out to be stable partners in the same way that you guys have been.”

The US has ruled out Hungary as a possible host country because its Government is too close to Russia, which objects strongly to the prospect of a US military presence in Central Europe.

Opposition is now growing, however, within Poland and the Czech Republic. Lech Kaczynski, the right-wing and populist Polish President, has objected publicly to the US establishing a sovereign military installation that would not be subject to local legal scrutiny. “I approach this problem with reserve, I won’t hide that,” he said recently. Almost two thirds of voters oppose the idea of the first foreign troops on Polish soil since the Soviet Army departed 15 years ago.

Polls suggest that a large majority of Czechs are also opposed to the idea. Jiri Paroubek, the Prime Minister, has expressed doubts about the scheme, suggesting that it should be subject to a nationwide referendum.

Jaap de Hoop Scheffer, the Nato Secretary-General, has also raised concerns about whether a system that protects only America might further undermine the creaking founding principles of an organisation committed to mutual defence.

Although there remain doubts about the operational effectiveness of the US missile defence system, pressure to go ahead with it has increased in the past year with North Korea obtaining nuclear capability and Iran apparently hell-bent on following suit.

Interceptor sites have been established in Alaska and California, and Congress recently approved $56 million (£30 million) in preliminary funding for a European base.

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