Britain was left scrambling to assert the vestiges of its colonial authority yesterday after Bermuda welcomed in four former Guantánamo detainees under a secret deal with the United States.

British officials knew nothing of the arrangement until the men, all ethnic Uighurs from western China, were already airborne en route from Guantánamo to the British island territory, better known as a haven for tourists and tax exiles than former terrorist suspects.

Alarm bells sounded in London when Ewart Brown, the Bermudian Premier, welcomed the men as “landed in Bermuda in the short term, provided with the opportunity to become naturalised citizens and thereafter afforded the right to travel and leave Bermuda, potentially settling elsewhere”.

The men are in the country as “guest workers”. Under the British Overseas Territory Act of 2002, citizens of Bermuda were restored with the full rights of British citizenship, including the right of abode in the United Kingdom. Bermuda has control over internal affairs, including immigration, but not over foreign affairs, defence or security matters, under which, London made clear, the case of the Uighurs falls.

In a statement shortly after their arrival in Bermuda, the Foreign and Commonwealth Office chided authorities there for failing to consult London on their decision to admit the men and insisted that security assessments must be carried out before their future was decided. “This was a decision of the Bermuda Government,” the FCO said.

“We have underlined to the Bermuda Government that it should have consulted the UK on whether this falls within their competence or is a foreign affairs or security issue for which the Bermuda Government do not have delegated responsibility.”

The Foreign Office noted that the Uighurs — Huzaifa Parhat, Abdul Semet, Abdul Nasser and Jalal Jalaladin — do not possess any travel documents and so would be unable to leave Bermuda.

A spokesman declined to say whether Britain would have intervened earlier had it known of the deal, saying: “We will be working with the Bermuda Government to decide further steps as appropriate. It’s something that we should have been consulted about.”

The development comes after Washington’s failure to convince Britain to take any more former detainees from Guantánamo as part of the Obama Administration’s effort to close the Cuban-based jail. Britain believes that it has “done its bit” after accepting 13 British citizens and residents released from Guantánamo.

It was reported on Wednesday that the 17 Uighurs, long recognised as not an international terrorist threat, would be resettled in the former American dependency of Palau in the South Pacific.

Four of their number proclaimed their delight yesterday at tasting freedom in a quite different island paradise as they landed at Hamilton international airport.

Bermuda accepts the Uighurs in defiance of enormous diplomatic pressure from China, which has demanded the return of the men to be tried as terrorists fighting to liberate Muslim-majority Xinjiang from Chinese rule. The US has refused to repatriate them to China for fear that they would be tortured or executed.

It emerged last night that senior US officials accompanied the four Uighurs on their flight to Bermuda, underlining the mission’s importance to the Obama Administration. Officials said that Greg Craig, a White House counsel, and Daniel Fried, special envoy overseeing the closure of Guantánamo jail, were on board.

Sabin Willet, a lawyer accompanying the men, hailed Bermuda for its “act of grace”. He said: “Nations need good friends. When political opportunists blocked justice in our own country, Bermuda has reminded her old friend America what justice is.”

Those words will smart in London, where questions are already being asked why the US felt free to consult Bermuda but not Britain on the deal. Comparisons have been raised with the Bush Administration’s covert use of another British territory, Diego Garcia, for the extraordinary rendition of terror suspects without British knowledge — leading to an embarrassing climbdown in Parliament for the Foreign Secretary, David Miliband.

The 1983 US invasion of the former British dependency of Grenada moved the Queen to a rare public rebuke of Washington for its attack on her Commonwealth realms.

While Britain remains its colonial master, Bermudian trade and economic relations with the US have become increasingly important. Its Government is eyeing warily President Obama’s moves against tax havens and is anxious to stave off regulations.

Local residents predicted that the Uighurs would cause fewer ructions with the 70,000 inhabitants of the archipelago. “They are unlikely to get involved in too much political strife. The big debate here at the moment is whether or not to allow gambling on cruise ships,” James Whittaker, of The Bermuda Sun, said. “It sounds like they are free to come and go as they please so, like most visitors on their first week in Bermuda, they’ll probably head to the beach.”

After that the future is not yet clear. In his statement Dr Brown acknowledged that the final decision over the Uighurs rested with the crown-appointed Governor. He did his utmost to make their arrival sound like a done deal.

“Those of us in leadership have a common understanding of the need to make tough decisions and to sometimes make them in spite of their unpopularity, simply because it is the right thing to do,” Dr Brown said. “We await a decision . . . in many respects the international community awaits a decision. But, in the meantime, I can say on behalf of the government, we are confident this decision is the right one from a humanitarian perspective.”

Worlds apart

Bermuda

GDP per capita $91,477 (£55,000) — the highest in the world

Land mass 138 islands covering total of 20sq miles (53sq km)

Population 70,000

Xinjiang Uighur Autonomous Region

GDP per capita 15,000 yuan (£1,326). 2.2 million people live below the poverty line

Land mass 640,000sq miles (1,664,900sq km); landlocked

Population 21 million

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