The European Commission effectively delayed by three months on Tuesday any decision on whether to introduce visa requirements for U.S. and Canadian citizens by asking EU member states and the European Parliament to discuss their stance.

The EU executive had signalled it was considering such a move on visas in the midst of difficult negotiations with the United States on a multi-billion dollar transatlantic trade pact.

The European Union's visa policy is based on reciprocity and the United States and Canada currently require visas for citizens of several EU member states including Poland, Romania and Bulgaria.

"The Commission is ... today inviting the European Parliament and the (European) Council (of member states) to urgently launch discussions and to take a position on the most appropriate way forward... and to inform the Commission on their respective positions by 12 July 2016 at the latest," the EU's executive arm said in a statement.

Any move to slap visas on Americans and Canadians is seen as unlikely due to political considerations as well as the negative effect it would have on Europe's lucrative tourism industry.

"It is important that the European economy does not become a victim," European Tourism Association ETOA said in a statement.

"The business of accommodating U.S. and Canadian visitors is an enormously important industry for Europe. We effectively sell them services worth approximately 50 billion euros ($56.87 billion)... Millions of jobs are dependent on it."

The ETOA estimated that introducing visas for citizens of the two countries would cut a third of leisure travels to Europe, which make up more than 80 percent of all trips.

Britain, which will hold a referendum on its continued membership of the EU in June, has an opt-out from the EU's common visa policy. Ireland is also outside the common policy.