Portugal's new centre-right government said Friday a Portuguese referendum on a proposed European Union constitution was only a possibility, contrasting with a firm commitment by the previous administration to hold a vote on the project.

Former prime minister Jose Manuel Barroso, who resigned this month to become head of the European Union Commission, told parliament exactly a month ago on June 23 his government had begun steps to prepare a referendum in 2005 on the constitution.

He said the exact date for the vote would be suggested after the summer recess.

But a program for the next two years presented to parliament Friday by the new government spoke only of educating the public about the constitution and its implications, "with a view to a possible referendum on the issue".

The program was presented by the new Prime Minister Pedro Santana Lopes.

Referendums in Portugal traditionally suffer from extremely low voter turnout.

In the most recent referendum held in 1998 only 31 percent of all eligible voters participated, voting by a slim margin to keep the nation's highly restrictive abortion laws in place.

The EU constitution must be ratified by all member states either through referendums or via simple vote in parliament by October 2006.

France, in a surprise move earlier this month, joined Britain in announcing a vote on the treaty bringing to seven the number of EU members who have announced they will put the document to a referendum.

If any one, particularly a big power like Britain of France, rejected it the whole constitution project would be thrown into doubt.