The European Union launched talks on closer political and economic ties with Libya, part of a drive to boost relations with energy suppliers.

The envisaged framework agreement covers areas ranging from trade to energy, illegal migration and the environment, the EU's executive Commission said.

EU ties with Libya were stalled for years over charges that the Libyan government supported terrorism. But Brussels announced in July it would boost relations after Tripoli freed Bulgarian medics accused of infecting Libyan children with HIV.

"Libya is the last south-Mediterranean country with which the EU has no contractual relations and we are keen to establish a clear, long-lasting legal framework," EU External Relations Commissioner Benita Ferrero-Waldner said in a statement.

Talks with Libya would aim for cooperation on foreign policy and security issues, a free-trade area that is "as deep and comprehensive as possible", and cooperation in areas including maritime policy and fisheries, the Commission said.

Europe takes the bulk of Libya's oil exports and European firms are keen to expand energy investment there. The EU also wants Libya to help in sea patrols aimed at stemming a flood of illegal migrants from Africa.

In the deal struck to secure the liberation of the medics, the EU held out the prospect of increased market access for Libya in fisheries and agricultural products, as well as cooperation on migration and tourism.

The European Union did not insist on the negotiations being conducted under the EU's so-called Barcelona Process, which Libya has appeared reluctant to embrace given requirements for political and economic liberalisation.

However, the EU statement said fundamental principles underpinning the agreement would be respect for human rights and democracy, the non proliferation of weapons of mass destruction and commitment to the rules of the market economy.