The DUP said it was not ideologically opposed to a Lib-Lab agreement but would vote in the interests of NI.
The SDLP said it would prefer an agreement between Labour and the Liberal Democrats.
Gordon Brown, who is to step down as Labour leader, said talks with the Lib Dems were in the "national interest".NI parties react to Brown announcement
BBC Northern Ireland political editor Mark Devenport explained the potential role for Northern Ireland MPs in a coalition.
"If Labour did a deal with the Liberal Democrats, they would have a parliamentary strength of 315," he said.
"That is 11 short of the formal margin for a Commons majority of 326 but the absence of the five Sinn Fein MPs lowers the effective margin to 324.
"If all the 13 remaining Northern Ireland politicians decided to back a Labour and Liberal Democrat government, that would take a Labour and Liberal Democrat government to 328, enough for a very small majority."
Doubt
DUP deputy leader Nigel Dodds said that his party was not ideologically opposed to a deal between Labour and the Liberal Democrats.
"We would only be prepared to look at things on a case by case basis," he said.
"We have always said that we would only do so on the basis of Northern Ireland's interests being protected in terms of the block grant, the economy and so forth."
Alasdair McDonnell of the SDLP said his party would prefer a Lib-Lab deal "because of the horrific memories of the Conservatives under Thatcher".
He added that his party believed David Cameron was planning "slash and burn" cuts.
Some Labour figures have expressed doubt about a "rainbow coalition".
The former Northern Irelan secretary John Reid argued that if Scottish and Northern Irish politicians were offered special deals, resentment could build up amongst English voters.
Mr Reid argued they may feel they are taking the brunt of any future cuts.
Block grant
Meanwhile, Stormont party leaders have discussed reaching a common position on the NI block grant as their MPs' votes could be vital in forming a new government.
A meeting took place on Monday, attended by the Sinn Fein president Gerry Adams, the SDLP leader Margaret Ritchie and David Ford of Alliance.
Both unionist leaders sent their apologies.
It is understood the matter is likely to be discussed at a meeting of the Stormont executive on Thursday.
During First Minister's Questions in the Assembly on Monday, the new Alliance MP for East Belfast, Naomi Long, suggested that the 13 MPs intending to take their seats should seek common ground on defending Northern Ireland's interests.
She said: "We are not the only people who are outside the main block they could be approaching looking for support so it's hugely important that when they do that, they come to a coherent group who actually know what they stand for.
"I think all the parties who were elected here with MPs wanted to put things like the economy ahead of their own agenda."
sports
I like it
sports
where am i?
your best friend
http://forum.computertotaal.nl/phpBB2
http://www.torchinese.com/bbs
http://www.animeacademyradio.net/forum
http://www.windsorsafaripark.org.uk
http://forum.radiojozef.pl
