Cairo: The US ambassador to Yemen on Thursday urged Iran-backed rebels in the war-torn country to show “political maturity” and live up to their responsibilities under a UN-negotiated peace deal for the port city of Hodeida, Yemen’s key gateway for international aid.

The remarks by US Ambassador Matthew Tueller came a day after the spokesman for Yemen’s internationally-recognised government called for stepped-up international pressure on the rebels, known as Al Houthis, who have refused to surrender Hodeida.

Speaking in the southern city of Aden, which has been serving as the seat of Yemen’s government since the rebels in 2014 seized the capital of Sana’a, Tueller asked Al Houthis to stop serving the interests of those who want to further “weaken” Yemen - a veiled reference to Iran.

Tueller said he is hoping “to see if Al Houthis can demonstrate political maturity” and urged them to stop serving Iran’s agenda and instead “start to serve the interest of the Yemeni people.”

On Wednesday, Rajeh Badi, the Yemeni government spokesman, denounced remarks by senior rebel leader Mohammad Ali Al Houthi who earlier this week told The Associated Press that a rebel withdrawal from Hodeida would be “impossible.”

Badi said such remarks could set off new fighting in Hodeida and violate the tentative peace agreement reached by the two sides in Sweden late last year.

The remarks are a “renunciation of the Hodeida agreement and a declaration of war,” Badi said, urging the UN to prevent another “explosion of the situation” in Hodeida.

The government fears Al Houthis are using the current Hodeida ceasefire to dig in and plant land mines ahead of another round of fighting, he said.

Renewed all-out war in Hodeida would risk severing the main passage for humanitarian aid to the rest of the country, including northern Yemen, the Al Houthi heartland.