The prime minister was urged to support a United Nations resolution demanding an immediate ceasefire in the war-torn country after the US ramped up pressure by calling on both the Saudi-led coalition and the Houthi rebels to end their airstrikes.
Ms May told MPs that the UK supported calls for “de-escalation” in Yemen but the government’s position remained that a ceasefire would only work if there is a political deal between the conflict parties.
It comes as US defence secretary James Mattis said all parties must come to the negotiating table within 30 days, while Mike Pompeo, the secretary of state, went further by demanding an end to the bombing campaign by both sides.
Raising the point at prime minister’s questions, Tory ex-cabinet minister Andrew Mitchell, said: “Following the welcome call overnight from the American administration for the ending of the Saudi bombing campaign in Yemen, will you use Britain’s undoubted authority at the UN to press for a new Security Council resolution demanding an immediate ceasefire, and meaningful and inclusive negotiations to end what is the worst and most terrifying humanitarian catastrophe on the planet?”
Ms May replied: “We certainly back the US call for de-escalation in Yemen.”
She said the UK had coordinated a UN statement calling on the parties to agree steps towards a ceasefire earlier this year, adding: “This remains our position.”
“As the foreign minister [Alistair Burt] said in the House yesterday, a nationwide ceasefire will only have an effect on the ground if it is underpinned by a political deal between the conflict parties.”
Foreign secretary Jeremy Hunt discussed the matter with the UN special envoy Martin Griffiths last night, and agreed that the UK will continue to encourage both sides to agree to de-escalation and a “lasting political deal to ensure the ceasefire will hold in the long term”, she said.
In some of the strongest words on the conflict from US officials, Mr Pompeo said: “The time is now for the cessation of hostilities, including missile and UAV strikes from Houthi-controlled areas into the kingdom of Saudi Arabia and the United Arab Emirates.
“Subsequently, coalition airstrikes must cease in all populated areas in Yemen.”
Labour criticised the government for failing to support the calls and condemned the UK’s support for the Saudi-led coalition in Yemen.
A spokesman for Jeremy Corbyn said: “It’s quite clear that the prime minister is not supporting the call for an urgent ceasefire by the US administration, which has called for a ceasefire within 30 days.
“It highlights the role the British government has played in supporting the Saudi-led coalition’s bombing of Yemen and the advice given to the Saudi military by British forces.”
Shadow foreign secretary Emily Thornberry said she was “heartened” by the US stance but claimed that the UK had a “culpability” over the war by supporting arms sales to Saudi Arabia.
“Two years ago there was an appalling airstrike by the Saudis on a wedding, it was said that this was never going to happen again, things were going to be sorted out, everything was going to change and at that point Britain had a draft resolution for a peace settlement, for a ceasefire, and it was about to be put on the table and then it was pulled,” she told the BBC’s World At One.
“We understand from the Saudis, and the Saudis are quite open about this, that they had come to an agreement with the British that they would keep the matter under review but at the moment the peace resolution was not going to be put on the table.”
It comes after the government was accused of being “complicit” in creating a famine in Yemen because of its support for the Saudi-led coalition.
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