The UN Security Council on Friday gave its approval to a European military operation to seize and dispose of boats run by migrant smugglers in the Mediterranean off Libya's coast.
A British-drafted resolution won UN backing as Europe struggles to mount a response to its worst refugee crisis since World War II.
The 15-member council adopted the measure by a vote of 14 in favor, with Venezuela abstaining.
European warships on Wednesday launched Operation Sophia to seize traffickers' boats in international waters and stem the tide of migrants making the perilous journey across the Mediterranean.
The UN mandate given to the naval task force was not mandatory for the European Union to take action but does provide Operation Sophia with greater legitimacy.
"Today's resolution is a small part of the solution to a huge challenge," British Ambassador Matthew Rycroft told the council.
A five-nation naval task force comprised of an Italian aircraft carrier, two French and British frigates and two German ships launched the second phase of Europe's response to the Mediterranean migration crisis.
The first phase of the operation, which involved monitoring trafficker networks and rescuing refugees from rickety boats crossing the Mediterranean, has been running since June.
The resolution authorizes European naval forces to board ships for inspection, seize them and even dispose of vessels suspected of being used by migrant smugglers.
The measure was adopted under Chapter 7 of the UN charter, which authorizes use of force, but it limits the UN mandate to a period of one year.
It does not authorize action in Libyan territorial waters or on the country's coast, which the European Union wants to carry out in the third phase of its anti-trafficking plan.
Europe hopes that smashing the refugee trafficking networks will help save lives and deter asylum-seekers from making the dangerous journey.
Around 3,000 people have died while crossing the Mediterranean to Europe this year, while over half a million have made the voyage, mostly landing in Greece and Italy.
Presented to the Security Council last month, the resolution faced initial resistance from African countries while Russia raised questions about the measure.
Venezuela opposed it from the outset for authorizing the use of force.
Venezuela's Ambassador Rafael Ramirez told the council that Europe's migrant crisis was "being tackled in an erroneous fashion" by resorting to military force.
"It's not by raising walls or taking military action that this serious problem can be resolved," he said.
African countries and Russia changed their stance after Libya's internationally-recognized authorities said they had dropped their opposition resolution.
Libya's Ambassador to the United Nations Ibrahim Dabbashi sent a letter to the Security Council on Tuesday stating that Libya "is no longer objecting" to the resolution.
Libya's consent was delivered as UN-led talks on forming a new unity government in Tripoli were making some headway.
The United Nations hopes that a new power-sharing agreement will allow Libya to tackle human-trafficking gangs on its territory which are fueling Europe's migrant crisis.
On Thursday, Libyan authorities said they had arrested some 300 migrants as they were preparing to board boats.
As Europe stepped up resettlement of migrants, UN refugee chief Antonio Guterres warned of looming tragedy if thousands of people are caught on the move when winter hits.
More than 600,000 people have flooded into Europe so far this year, mainly arriving by boat in Greece and Italy.