If the US Congress brands the 1915 mass killing of Armenians by Ottoman Turks a "genocide", it will damage relations with Turkey and ensure Ankara keeps up its blockade of Armenia, a senior Turkish lawmaker said on Tuesday.
Ankara could also consider restricting the US military's use of Incirlik air base, a logistics hub for the Middle East, parliamentarian Mehmet Dulger told Reuters.
The Bush administration opposes the resolution on the events in 1915 as the Ottoman Empire broke apart but the US Congress is now dominated by the Democratic Party and has become more influenced by the Armenian diaspora.
Washington is keen to avoid antagonising Turkey, a Nato ally and moderate Muslim country whose support it needs in the region as it battles Iraqi insurgents and confronts Iran over its nuclear programme.
Dulger, head of the Turkish parliament's foreign affairs committee, also said passage of the resolution would have ramifications for Armenia by spurring Ankara to keep up its blockade of the neighbouring state. "The economy of the Caucasus region is stirring, but the Armenians are being kept out of the game," he said.
He noted Armenia, a tiny, impoverished ex-Soviet republic, was already bypassed by oil and gas pipelines and rail links uniting Turkey to energy-rich Azerbaijan via Georgia.
Turkey shut its border with Armenia over Yerevan's seizure of land belonging to Ankara's Turkic ally Azerbaijan in the 1990s. It also objects to Yerevan's claims on some Turkish land and its insistence that 1.5 million Armenians suffered genocide at Ottoman Turkish hands in 1915 - claims Turkey denies.
Turkish media say that if Congress backs the bill, Ankara might also crack down on some 70,000 Armenians working illegally in Turkey, whose remittances help support the economy back home.
Dulger, a member of the ruling centre-right AK Party, said Turkey had not yet decided what measures it might take to "punish" the United States over the bill, but added: "Incirlik is one possible area which could be affected." Turkish sources say some 80 percent of the logistical goods used by US troops in Iraq pass through Turkey and many of the items are produced in Turkey.
"(Passing the bill) would be an act of hostility for us and would deliver a greater blow to our relations with Washington than the Turkish parliament's refusal (in March 2003) to allow American troops to cross our territory to invade Iraq." That decision, which analysts say hampered the US drive to oust Saddam Hussein, triggered a lengthy chill in relations.
Turkey is going all out to stop the resolution. In the last month alone, it has sent its foreign minister, army chief and two delegations of lawmakers to Washington. Members of Congress are also being bombarded with emails from Turkish citizens urging them to oppose the bill. But Dulger said he was pessimistic any of this would work. "I think the resolution will pass because of support from (new House of Representatives speaker Nancy) Pelosi," he said. The resolution would stoke anti-US sentiment in Turkey and boost ultra-nationalists ahead of this year's parliamentary elections, said Dulger, from the ruling centre-right AK Party.