'The lifting of the embargo may now take longer, perhaps until 2006, and the EU could consider an alternative regime on arms sales to China,' said Willem van der Geest, director of the Brussels-based European Institute for Asia Studies.

Dr Rice expressed US opposition to the lifting of the ban during meetings with top EU officials during a visit last week. The mission was an effort to improve transatlantic relations and prepare for US President George W. Bush's visit to Europe at the end of the month.

'I really have to underscore how much the Europeans have tried to take account of our concerns. We are having fruitful discussions with our European allies ... I do feel we are being listened to,' she said.

The lifting of the embargo, imposed in the aftermath of the 1989 Tiananmen Square crackdown, was first proposed by Germany and France. Beijing has described the restrictions as outdated and discriminatory, pointing out the only other nations prohibited from buying European arms are Myanmar, Zimbabwe and Sudan.

Washington, however, opposes lifting the embargo on human rights grounds and because of its potential to destabilise regional security.

To press its point, the US Congress recently threatened to impose sanctions on European companies that sell arms to the mainland, and warned military co-operation between the US and Europe would be significantly reduced.

Mr van der Geest said such US pressure had caused the EU to continually delay its decision, noting the ban was originally expected to be lifted in the first half of last year.

He added that nations that held the EU's rotating six month-presidency were particularly afraid to end the ban because they did not want to be seen to be challenging Washington. Luxembourg is the current EU president, to be followed by Britain.

Adam Ward, senior fellow for East Asian security at the London-based Institute of International Studies, said Britain was reluctant for the decision to be made under its presidency because it was Washington's closest ally.

'It is politically inconvenient for the British to have this hot potato fall on their lap.'

Analysts said the US pressure was adding to the EU's internal debate on the code of conduct that would govern the scope of sales once the embargo is lifted. The bloc is expected to impose restrictions on the type of weapons and technology to be made available.

It is also seeking more concessions on human rights issues from Beijing, such as more substantive dialogue, the release of political prisoners and co-operation on legal reform.

But in the end, analysts said the US lobbying and threats would be futile because it was only a matter of time before the EU lifted the ban.

During a press conference with Dr Rice, European Commission president Jose Manuel Barroso said: 'We are moving towards lifting the arms embargo. The European Union cannot be accused of rushing into this.'

Mr Ward said he believed that despite its reservations, Britain would end the sanctions if Luxembourg failed to do so during its EU presidency, because it did not want to damage Sino-British relations and its position within the European alliance.

'There is no ducking it for Britain,' he said. 'The trajectory is fixed and the US will not be able to prevent the lifting of the arms embargo.'