Recep Tayyip Erdogan, Turkey's prime minister, has threatened to expel thousands of illegal Armenian workers amid tensions over allegations that their people were victims of genocide under the Ottoman Empire.
Resolutions voted recently in the United States and Sweden to brand the World War I killings as genocide undermined peace efforts with Armenia, Erdogan told the BBC Turkish service.
Referring to about 100,000 Armenians working illegally in Turkey out of a total of 170,000 living there, Erdogan said: "Only 70,000 of them are Turkish citizens, but we are tolerating the remaining 100,000.
"If necessary, I may have to tell these 100,000 to go back to their country because they are not my citizens. I don't have to keep them in my country."
Forced to leave their impoverished country to earn a living, thousands of Armenians, mostly women, have settled in Turkey, mainly in Istanbul.
Many came after an earthquake in their homeland in 1988 and work illegally, mainly in manual jobs or as nannies and cleaning ladies, sending remittances home.
"So what will I do tomorrow? If necessary, I will tell them 'come on, back to your country'."
Erdogan blamed the genocide resolutions on the influential Armenian diaspora in the US and Western Europe.
"We are extending our hand, but if our counterparts clench their hand into a fist, there will be nothing we can do," he said.
"Those people make shows with those resolutions ... And they harm the Armenian people as well ... And things become deadlocked.
"Those actions [on genocide resolutions] unfortunately have a negative impact on our sincere attitudes."
Following Swiss-brokered talks to end decades of enmity, Turkey and Armenia signed an accord in October to establish diplomatic ties and open their border.
The process, however, has hit snags, with both countries accusing each other of lacking true commitment to the deal.
The climate was further inflamed this month when the US House Foreign Affairs Committee approved a non-binding resolution branding the massacres of Armenians a genocide, with the Swedish parliament following suit last week.
Turkey recalled its ambassadors from both countries, warning that bilateral ties and reconciliation efforts with Armenia would suffer.
Armenians say up to 1.5 million of their kin perished in a systematic extermination campaign during World War I as the Ottoman Empire fell apart.
Turkey counters that between 300,000 and 500,000 Armenians, and at least as many Turks, were killed in civil strife when Armenians rose up against their Ottoman rulers and sided with invading Russian forces.
Parliaments in several other countries have also recognised the mass killings as genocide in the past.