Supporters of a resolution in the US Congress to label as genocide the mass killing of Armenians in Turkey after 1915 have called for it to be delayed.
House Speaker Nancy Pelosi has long advocated such a vote
The four main sponsors of the vote said they still believed a majority of their colleagues would support it, but only if the "timing is more favourable".
House Speaker Nancy Pelosi said she respected their decision to postpone.
Turkey recalled its envoy over the vote and President George W Bush warned it could damage ties with the US ally.
The four Democrat co-sponsors of the resolution - Adam Schiff, Brad Sherman, Anna Eshoo and Frank Pallone - said they planned to table it again later this year or in 2008.
The vote had seemed ready for consideration by the House of Representatives after it was passed by the House Foreign Affairs Committee earlier this month.
Turkey, an important regional operational hub for the US military, accepts many Armenians died during World War One, but denies they were victims of systematic genocide.
Analysts say Ankara could deny American access to Incirlik airbase, or other supply lines crucial to US forces in Iraq and Afghanistan, in response to the passage of such a vote.