The UK government has insisted the EU treaty is not dead
Gordon Brown has said EU leaders must agree to give Dublin "time to reflect" on its next steps over the EU treaty.
Voters in the Irish Republic - the only state to hold a referendum - rejected the treaty, which must be ratified by all 27 EU members, on Friday.
Foreign Secretary David Miliband, after meeting EU colleagues, told MPs that ratification in the UK would go ahead.
Shadow foreign secretary William Hague said the UK should halt ratification and make clear the treaty was finished.
The Bill to ratify the treaty is nearing the end of its progression through Parliament.
The House of Lords is due to hold the third reading of the Bill on 18 June.
There has been a long running campaign for there to be a British referendum on the treaty, which was drawn up after the EU constitution was killed off by referendum defeats in France and Holland.
A referendum had been promised by all the main parties on the constitution, but UK ministers have said a referendum was not needed on the EU treaty, claiming it did not have constitutional implications.
The Conservatives led calls for a referendum on the treaty, saying that it was virtually identical to the abandoned constitution.
During exchanges in the Commons Mr Hague said the Irish people had been "courageous" in the face of threats from some EU politicians.
And the republic had displayed true democracy by holding a referendum, adding that the result - 53.4% of Irish voters voted "no" - should be respected.
"Is it not now clear beyond that there is profound opposition among the peoples of Europe over the substance of this treaty?" he added.
Mr Miliband said the rules of the treaty and the EU were clear - "all 27 member states must ratify the treaty for it to come into force".
"There is no question of ignoring the Irish vote or bulldozing Irish opinion," he said.
However, he added: "The government believes ratification should proceed as planned."
For the generally pro-EU Liberal Democrats, foreign affairs spokesman Ed Davey said the UK should not pre-judge what might happen at the meeting of EU leaders later this week.
He asked Mr Miliband whether the government intended to withold "despositing the instrument of ratification in Rome" until after the EU summit.
Mr Miliband did not say whether the UK would do so. He said that for the treaty to be ratified all 27 states would have to deposit their "ratification articles" in Rome and "clearly that will not happen before the European Council thisThursday and Friday".
Mr Davey said the EU had worked adequately in recent times, so with or without the Lisbon treaty, the focus should now move on to concentrating on issues like economic reform and tackling terrorism.