Airport officials in Yemen's capital Sanaa say a plane meant to carry Shiite Houthi rebels and their allies to talks in Geneva has left without the delegates on board.

A Houthi representative, speaking on condition of anonymity because he was not authorized to brief reporters, said Saturday that the Houthis objected to the idea of two separate delegations to the talks--one representing the embattled government, and one seen as representing a "coup."

He says this arrangement created an environment aimed at pressuring the Houthis to withdraw from Sanaa, rather than continuing a broader multi-party discussion. The Houthis had initially welcomed the meetings.

U.N. sponsored talks on the Yemeni conflict were scheduled to start on Sunday.