The U.N. Security Council has unanimously adopted a resolution allowing the European Union's maritime force off Libya's coast to seize illegal weapons helping to fuel violence and instability in the North African nation.

The British-drafted resolution adopted Tuesday authorizes EU ships in Operation Sophia that are now charged with seizing migrant-smuggling vessels to also stop ships on the high seas off Libya's coast suspected of smuggling arms in violation of a U.N. arms embargo.

Libya slid into chaos following the 2011 toppling and killing of longtime dictator Moammar Gadhafi. Since 2014, the oil-rich country has been torn between two parliaments and governments with each backed by a loose set of militias and tribes.

A U.N.-brokered unity government is struggling to fight Islamic State militants and gain control of the country which is awash with weapons.