Euronext and Deutsche Boerse have been in talks before

It has also given up on negotiations with the London Stock Exchange (LSE) about a potential tie-up.

Euronext said the discussions with Deutsche Boerse and "other parties" were at an early stage.

In a separate move, US stock exchange operator Nasdaq said it had increased its stake in the LSE from 15% to 18.7%.

Stock exchanges are looking to merge as competition for business increases, fuelled by a shift into electronic trading.

A merged European exchange has more appeal as traders, investors and issuers are all keen to reduce transaction costs - especially in clearing and settlement.

There has been a spate of merger talks between exchanges both in and outside of Europe.

Revived talks

Deutsche Boerse - with whom Euronext held abortive merger talks in 2005 - declined to comment on the new round of talks with its Paris-based suitor.

The negotiations last year foundered on issues including the location of any merged firm.

Deutsche Boerse's chief executive, Reto Francioni, had demanded that the headquarters be in Frankfurt. Euronext, which operates exchanges in Paris, Brussels, Lisbon and Amsterdam, disagreed.

Since then, however, Mr Francioni has backed away from this demand.

Overseas interest

At the same time, the LSE has become one of the main targets for foreign firms, and its share price has surged as a result.

Although Nasdaq dropped a planned takeover of the LSE when a �9.50-a-share proposal was rejected, it subsequently bought a 15% stake in the company in a deal worth �447.7m ($780m).

On Wednesday, it said that it had spent �119.2m buying another 9.79 million LSE shares taking its stake to 18.7%.