BRUSSELS: Nearly half a million people displaced in Libya could travel to Europe, the EU’s foreign policy chief has told the bloc’s foreign ministers in a letter, urging action to prevent another escalation in the region’s migration crisis.

In the message seen by Reuters, Federica Mogherini warned that people traffickers were operating freely in Libya and said the EU was working on sending a civilian security mission to boost the country’s police, border forces and counter-terrorism operations.

The letter, sent on March 12, came in the build-up to a series of top-level meetings on the migration crisis, including one hosted by Britain in Brussels on Friday with Mogherini and leaders of France, Germany, Italy, Spain and Malta.

Diplomats and activists have said they are concerned Libya could be forgotten while the bloc focuses on reaching a deal with Turkey to return refugees from Greece. An effective deal with Turkey may also push traffickers to focus on other routes to smuggle migrants to Europe.

“There are more than 450,000 internally displaced persons and refugees in Libya who could be potential candidates for migration to Europe,” Mogherini wrote.

The European Union is working on helping Libya boost its institutions and on ensuring that a UN-backed government, currently based in Tunis, can operate from Tripoli.

The North African oil producer plunged into chaos after rebels ousted dictator Muammar Qaddafi in 2011, backed by British and French air strikes supported by US.

London and Paris struggled for months to win broader EU support for sanctions on three Libyan leaders seen as blocking the UN process to establish a government in Tripoli. They finally won support this week to go ahead with preparations to impose asset freezes and travel bans.