UN envoy to Yemen Martin Griffiths arrived in Sanaa on Wednesday for talks with leaders of the Houthi rebel group.

Griffiths' visit comes amid ongoing preparations for a fresh round of talks between Yemen’s warring camps.

It also comes amid mounting international pressure on both parties to reach a political solution to the country’s ongoing crisis.

Last Friday, Griffiths announced that both parties to the conflict had confirmed their intention to take part in planned peace talks in Sweden.

Griffiths’ announcement came after David Beasley, the head of the UN's World Food Program, warned that Yemen was facing a full-fledged humanitarian catastrophe.

The UN envoy is now expected to meet Houthi leaders “within hours”, according to an Anadolu Agency correspondent based in the region.

Impoverished Yemen has remained wracked by violence since 2014, when Houthi rebels overran much of the country, including capital Sanaa. 

The conflict escalated in 2015 when Saudi Arabia and its Sunni-Arab allies launched a devastating air campaign in Yemen aimed at rolling back Houthi gains.

Tens of thousands of people -- including numerous Yemeni civilians -- are believed to have been killed in the conflict, which has left much of the country’s basic infrastructure in ruins.