The UN envoy to Yemen left the rebel-held capital empty handed Thursday after a mission aimed at reaching an agreement for talks between the insurgents and the government.
"We have not set a new date for the next round of talks," Ismail Ould Cheikh Ahmed told reporters at Sanaa airport before departing the conflict-riven country.
The Mauritanian diplomat said he was alarmed by the "suffering of Yemenis", but he expressed hopes of a "quick return" to the negotiating table.
The Yemeni government sat down with the rebels and their allies last month in Switzerland for six days of talks that ended without a major breakthrough.
The envoy had met with government officials, who are temporarily based in Riyadh, before he headed to Sanaa.
Foreign Minister Abdel Malak Al Mekhlafi said Saturday that the talks initially scheduled to start on January 14 had been postponed until January 20 or 23.