A US Congressional committee is set to vote later on a resolution to label as genocide the killing of Armenians by Turkish forces during World War I.

The resolution is not binding, but if it is passed, it can go forward for a vote in the House of Representatives.

In 2007, a similar resolution passed the committee stage, but was shelved before a House vote after pressure from the Bush administration.

Turkey has warned of consequences for US-Turkey ties if it is passed.

A Turkish parliamentary delegation has gone to Washington to try to persuade members of the House Foreign Affairs Committee not to vote for a resolution calling for the recognition of "the Armenian genocide".

The non-binding resolution calls on US President Barack Obama to ensure that US foreign policy reflects an understanding of the "genocide" and to label the World War I killings as such in his annual statement on the issue.

In 2007, the same committee passed a similar resolution on the issue, and even though the Bush administration had lobbied hard against it, Turkey was still furious, says the BBC's Kim Ghattas in Washington.

Turkey, a key Nato ally, recalled its ambassador from Washington and threatened to withdraw its support for the war in Iraq.

This time, the government in Ankara is even more worried because the Obama administration has not publicly come out against the move, our correspondent says.

Both Mr Obama and US Secretary of State Hillary Clinton have in the past supported the resolution as senators.

Nationalist sentiment is intense in Turkey, and if the resolution passes, there will be an emotional reaction, even by those who have been arguing for reconciliation with Armenia, says the BBC's Jonathan Head in Istanbul.

There will certainly be a gesture of disapproval by the Turkish government, or maybe something stronger - a worrying possibility for the Obama administration, which sees Turkey as a vital moderate Muslim ally, our correspondent adds.

Historic deal

In October last year, Turkey and Armenia signed a historic accord normalising relations between them after a century of hostility.

Armenia wants Turkey to recognise the killings as an act of genocide, but successive Turkish governments have refused to do so.

Hundreds of thousands of Armenians died in 1915, when they were deported en masse from eastern Anatolia by the Ottoman Empire. They were killed by troops or died from starvation and disease.

Armenians have campaigned for the killings to be recognised internationally as genocide - and more than 20 countries have done so.

Turkish officials accept that atrocities were committed but argue they were part of the war and that there was no systematic attempt to destroy the Christian Armenian people.