Ireland's Prime Minister Brian Cowen began talks Wednesday with key EU leaders on the European Union's stalled reform treaty, ahead of a crunch EU summit next week.

Cowen is mulling whether to hold a second vote after Irish voters rejected the Lisbon Treaty in a June referendum, plunging the 27-nation bloc into institutional limbo and putting plans for structural reform on hold.

The embattled Irish premier held talks with Luxembourg Prime Minister Jean-Claude Juncker before heading on to Germany.

No details of the closed-door meeting emerged as Cowen seeks to agree a strategy in time for an EU summit in Brussels on December 11-12.

He will also hold talks in Britain and France over the next two days.

Foreign Minister Micheal Martin warned Tuesday that talks on what to do about the Lisbon Treaty will go "down to the wire" at the summit.

Cowen is thought to be considering whether Irish voters would back the treaty in a new poll if guarantees were given on key concerns including abortion, tax and the republic's cherished military neutrality.

Those issues, as well as opposition to losing a permanent Irish EU commissioner in Brussels, were found by researchers to be behind the June 12 referendum rejection by 53 percent of voters.

And an opinion poll last month suggested that, with guarantees on those issues, the result could be reversed: 43 percent would vote "yes" in a new referendum while 39 percent would vote "no," according to the Irish Times/mrbi poll.

After leaving Luxembourg following his closed-door talks with Jean-Claude Juncker, Cowen was travelling on to Germany for talks with Chancellor Angela Merkel, his office said.

On Thursday, Cowen will meet with Prime Minister Gordon Brown in London and on Friday he will visit France for talks with President Nicolas Sarkozy, who holds the six-month rotating EU presidency.

"The Taoiseach's (prime minister's) discussions with his European Council counterparts will focus on the situation in relation to the Lisbon Treaty ahead of next week's European Council," his office said.

"Other EU issues, notably the climate change and energy package and the international financial crisis, are also likely to feature."

In 2001, Irish voters rejected the EU's Nice Treaty, but the result was overturned the following year in a second referendum when clarifying declarations were given by other member states.

Dublin is hoping it can do something similar this time -- notably seeking a guarantee from EU partners on retaining its commissioner in Brussels.

Irish leaders may also seek clarifying declarations that backing the treaty would not lead to the introduction of abortion, affect Ireland's military neutrality or its low corporation tax policy.

While Cowen flew off to discuss the treaty dilemma with EU counterparts, Ireland's three opposition parties have pressed for private briefings from the beleaguered premier.

Fine Gael leader Enda Kenny said the issue was a matter of national importance as "we are now becoming the butt of some anti-European pressure".

"I think it is very necessary that the government should be able to inform the parties here as to what the strategy is that the government intend to adopt to deal with this situation.

"We need to know what it is that the government propose to do when the Taoiseach (prime minister) goes out to Brussels next week to explain to the other heads of government what is the strategy for Ireland."