The EU has agreed to start considering membership applications submitted by Ukraine, Georgia and Moldova.

The decision by the 27 member states is the first step in a complex membership decision process that could drag on for years, AFP reported.

EU ambassadors have agreed to ask the European Commission for an "opinion" on the three countries' applications, French EU presidency officials said.

It can take years for the executive to give its opinion and then member states must unanimously agree for the applicant to officially become a "candidate". A process of reforms and negotiations then begins, usually taking at least a decade to complete.

EU leaders intend to discuss the applications this week at a summit in France on the Ukraine crisis.