What is the fine-grained topic of the following text: Yemen - The Houthi Ansruallah Movement accused the United States of being the main force behind Saudi Arabia's continued prosecution of the war, and was the main reason that the recent UN-sponsored peace talks broke down in Switzerland, this week. Only return the topic.
Houthi Movement's accusation of U.S.'s role in Saudi-led war and peace talks failure in Yemen.