The pair met in Vilnius on the eve of a NATO summit, after Erdogan declared that Turkey would not approve Sweden's bid to join the alliance without a revival of Ankara's EU ambitions.

In a tweet, Michel hailed a "good meeting", adding that they had "explored opportunities ahead to bring EU-Turkey cooperation back to the forefront and re-energise our relations."

Turkey has been a formal candidate to join the European Union since 2005, and an aspirant since long before that, but talks have long been stalled with little sign of life.

Separately, NATO member Turkey has been blocking Sweden's attempt to join the military alliance, accusing Stockholm of harbouring Kurdish activists accused by Ankara of terrorism.

On Monday, in a surprise move ahead of Tuesday's NATO summit, Erdogan linked the two diplomatic logjams, demanding that the NATO allies that are also EU members clear Turkey's path.

"First, open the way to Turkey's membership of the European Union, and then we will open it for Sweden, just as we had opened it for Finland," he said, before flying to Lithuania.

Once in Vilnius, Erdogan broke off talks with NATO secretary general Jens Stoltenberg to hold an unplanned one-on-one with the EU's Michel -- before then meeting Swedish premier Ulf Kristersson.