Gay Alcorn, Washington – The Clinton administration said today that, on a practical level, it was too late for an armed United Nations peacekeeping force to enter East Timor before Monday's historic ballot, but said nothing about the possibility of a force immediately after the vote.

The administration is under pressure from influential members of Congress with strong interests in human rights in East Timor to push for a peacekeeping force, rather than rely on Indonesian authorities to maintain the peace. There are UN civilian police and military liaison officers in the territory, but not an armed multinational force.

A State Department spokesman, Mr James Foley, said: "We don't believe that the dispatch of armed UN peacekeepers before 30August is possible at this point."

Mr Foley was responding to calls from a senior Democrat Senator, Mr Tom Harkin, who last week led a Congressional delegation to East Timor, for President Clinton to recommend to the UN "that they get some peacekeeping forces down here in a hurry".

Mr Foley said that the administration had been concerned very much about the security situation in East Timor in past months. "We want the vote to be a free and fair vote, an honest reflection of the will of the people of East Timor," he said.

"In a more fundamental sense, we believe this is the responsibility of the Government of Indonesia, and we don't want to take that responsibility away from them," he added.

Senator Harkin was a co-sponsor of an amendment passed in the US Senate in June which is expected to become law next month. The amendment raised the prospect of withholding aid money to Indonesia if it fails to control pro-Government militia groups responsible for widespread violence in East Timor.

Although the UN is developing plans for a force, it would not be in place until at least four months after the ballot, which many observers believe will be too late to avoid violence.

The assistant secretary of State for East Asian and Pacific Affairs, Mr Stanley Roth, is due in Australia this week. As the administration's most senior policy adviser on Asia, Mr Roth is considered influential with President Clinton and committed to a smooth transition in East Timor.

Earlier this year, Mr Roth met the head of Australia's Foreign Affairs Department, Dr Ashton Calvert, when, according to a record of the meeting, Mr Roth said Australia's aversion to a peacekeeping force was defeatist. Both governments have denied any policy rift over East Timor.