The Government has been given the go-ahead to appeal to the UK’s highest court against a ruling that its decision to continue licensing military equipment for export to Saudi Arabia was unlawful.

Campaign Against Arms Trade (CAAT), which brought the case against International Trade Secretary Liam Fox, hailed a landmark legal victory last month.

The group argues that the decision to continue to license military equipment for export to Saudi Arabia, which is leading a coalition of forces in the conflict in Yemen, was unlawful, as there was a clear risk that the arms might be used in a serious violation of international humanitarian law.

The Court of Appeal ruled that the Government “made no concluded assessments of whether the Saudi-led coalition had committed violations of international humanitarian law in the past, during the Yemen conflict, and made no attempt to do so”.

CAAT announced on Friday that the Government had been granted permission to appeal against that ruling to the Supreme Court.

The group said the Supreme Court had also rejected the Government’s application to lift a temporary block on new export licences, which it said means that the more than 50 outstanding applications will not be determined while the Government re-evaluates the legality of current licences.

Andrew Smith of CAAT said: “We are disappointed that the Government has been given permission to appeal, but we welcome the Supreme Court’s decision to uphold the current ban on arms sales.

“These arms sales are immoral, and we are confident that the Supreme Court will agree they are also illegal.

“Despite the atrocities that have been inflicted in the terrible war on Yemen, this case, and the response, make clear that the Government will do anything it can to keep arming and supporting the brutal Saudi regime.

“UK-made weapons have played a central role in creating the worst humanitarian crisis in the world. The Government must stop the arms sales and end its role in the destruction.”

Rosa Curling, a solicitor with Leigh Day, which represents CAAT, said: “The decision of the court to refuse a ‘stay’ is welcomed.

“This means no new licence applications can be granted by the Government pending reconsideration of whether there exists a ‘clear risk’ that exported weapons ‘might’ be used in serious violation of international humanitarian law, in line with the approach required by the Court of Appeal.”

Lucy Claridge, director of strategic litigation at Amnesty International, which has intervened in CAAT’s case, said: “It was a rare piece of good news when the Court of Appeal ruled to block UK arms sales to Saudi Arabia, and we very much hope the Supreme Court will rule the same way.

“UK weapons have been fuelling a conflict which has had devastating consequences for Yemeni civilians.

“During the past four years, the Saudi Arabia-led coalition has killed thousands of Yemeni civilians – flattening homes, schools and hospitals in indiscriminate airstrikes.

“The Government should have halted arms sales to Saudi Arabia of its own volition years ago, but the courts will, we hope, force ministers to finally accept that these sales are wrong.”

The case will be heard by the Supreme Court on a date to be fixed.