LONDON (AP) — A British court ruled Thursday that the U.K. government acted unlawfully in selling weapons to Saudi Arabia that were used in the Yemen war, though it did not order a halt to the exports.

The Court of Appeal ruled in favor of anti-weapons campaigners, who argued that the sales should not have been allowed because there was a clear risk the weapons might be used in violation of international humanitarian law.

The British government plans to appeal the ruling, but while the case is ongoing, Trade Secretary Liam Fox said no new licenses for arms sales to Saudi Arabia would be granted.

Campaign Against Arms Trade argued that British bombs and fighter jets are fueling violence in Yemen, where a Saudi-led war against Iran-backed rebels has raged since 2015. The Gulf kingdom faces wide international criticism for indiscriminate airstrikes that have struck markets, hospitals and other civilian targets.

Three judges said the British government's decision-making "was wrong in law in one significant respect" — that they had "made no attempt" to find out whether the Saudi-led coalition had breached international law.

The judges said Britain should have investigated "whether there was an historic pattern of breaches of international humanitarian law on the part of the (Saudi-led) coalition, and Saudi Arabia in particular."

But the court's ruling does not mean existing arms-sales licenses must be suspended, only that the government "must reconsider the matter."

"We are carefully considering the implications of the judgment for decision making," Fox said after the ruling.

Andrew Smith of Campaign Against Arms Trade said "we welcome this verdict but it should never have taken a court case brought by campaigners to force the government to follow its own rules."

Britain is the second-biggest supplier of weapons to Saudi Arabia, after the United States.