A bipartisan group of senators on Wednesday asked the Bush administration to consider whether the US could take action via the United Nations if Uzbekistan does not allow an independent investigation into last month's massacre at Andijan.

In a letter to the Bush administration, four Republican senators - John McCain, Lindsey Graham, John Sununu and Mike DeWine - and two Democrats - Patrick Leahy and Joseph Biden - said the US should reconsider its relationship with Uzbekistan in light of the May 13 massacre, in which hundreds of civilians were reportedly killed by Uzbek forces.