ISTANBUL, Oct 12 (Reuters) - Turkish Prime Minister Tayyip Erdogan said on Friday relations between Turkey and the United States were in danger over a resolution branding as genocide massacres of Armenians by Ottoman Turks.

Referring to relations with the United States and the Armenian resolution, Erdogan, using a Turkish idiom usually employed to describe relations, said: "Where the rope is worn thin, may it break off." He did not elaborate.

The crowd of supporters broke into applause. The U.S. House of Representatives Foreign Affairs Committee approved on Wednesday a resolution branding the killings in 1915 genocide -- a charge Turkey hotly denies. Ankara responded by calling its ambassador back for consultations.