Britain has abandoned plans to arm Syrian rebels fighting to overthrow President Bashar Assad, lacking popular support for intervention amid concerns that the insurgency is increasingly radicalized.

Citing sources familiar with government thinking, the Reuters news agency reported on Thursday that the United Kingdom was wary of sending weapons into the conflict which could end up in the hands of Islamist militants.

Lawmakers passed a motion last week urging the government’s consultation of Parliament before shipping arms for just that reason.

“It will train them, give them tactical advice and intelligence, teach them command and control. But public opinion, like it or not, is against intervention,” said one source.

British prime minister David Cameron previously advocated deeper Western involvement in Syria’s civil war. His government, with France, lobbied other European Union member states earlier this year to relax the conditions of an arms embargo that prohibited weapons supplies to either side, worried that Iranian and Russian support for Assad’s forces tipped the balance of the war in his favor.

Support for the Syrian government from the Lebanese militant organization Hezbollah and divisions within the rebel camp — Kurdish and secular groups were outraged last week by the assassination of a rebel commander by Islamists — might also have changed Britain’s calculus. One of Reuters’ sources said the country now expects Assad might hold on to power for years.

President Barack Obama announced last month that the United States would start providing small arms to the rebels, after rejecting calls to interfere in the conflict for two years. But many lawmakers are skeptical and might block such efforts.

Western allies in the region, notably Qatar and Saudi Arabia, have armed Syrian opposition fighters, hoping that they will topple Assad who is the only Arab ally of their nemesis Iran. European powers and the United States have limited themselves to providing “nonlethal” aid, including communication and sanitation systems as well as body armor.