EU leaders may decide to scrap all other planned referendums on the bloc's new constitution during their summit later this month in the wake of its rejection by voters in France and the Netherlands, Portuguese Foreign Minister Diogo Freitas do Amaral has said.

"What may happen at the next European Council is that the leaders of the 25 member states could conclude that it would be a useless and even painful exercise if it appeared that successive referendums would produced more 'no' results," he told state television RTP late Thursday.

The referendums could either be temporarily suspended to give time for a period of relection or "the whole process could be terminated", he added.

"We can't be blind to reality and we can't pretend that nothing happened in France and the Netherlands, that nothing could happen with the British government. We can't act like an ostrich," said Freitas.

European Union leaders are expected to decide how to respond to French and Dutch rejections of the charter at their regularly scheduled June summit in Brussels, Belgium on June 16 and 17.

British Foreign Secretary Jack Straw is set to announce that Britain's referendum on the EU constitution will be put on hold, senior officials in London were quoted as saying Thursday.

Portugal has scheduled a vote on the charter -- meant to streamline decision-making in the expanding bloc -- for October.

"Officially we maintain that Portugal should be consulted through a referendum," said Freitas.

"But if there is a generalized consensus (in the EU to cancel or put on hold all future referendums), Portugal will certainly be a part of that consensus."

The EU constitution, which needs approval by all member states before taking effect, has so far been ratified by 10 countries including Austria, Greece, Hungary, Italy, Latvia, Lithuania, Slovakia, Slovenia, Spain and Germany.