A senior Liberal Democrat said "anything is possible" in the event of a hung parliament after the general election.
Treasury spokesman Vince Cable said his party did not rule out making a formal alliance with either Labour or the Tories and called for an end to "very narrow, short-term tribal politics".
His remarks followed a series of opinion polls predicting a hung parliament, in which the Lib Dems would be likely to hold the balance of power.
Mr Cable told BBC One's Andrew Marr Show: "We would act in a financially responsible way, we've made that very clear through our policies.
"Whoever we talk to, however the situation evolves, that's a secondary issue. It's not for us to choose."
Pressed on whether he would rather support a minority government than make formal alliances, he said: "We're not ruling things out. Anything is possible, parties can work together in different ways.
"It may well be that the public is really rather fed up with very narrow, short-term tribal politics and they want to see politicians rising above that, particularly as they sense we're in an economic crisis."
Voters expected politicians to be "grown-up and business-like" in their approach to working with other parties, he added.
But the Sunday Times reported that Lib Dem leader Nick Clegg would refuse to accept Gordon Brown as the leader of a minority government.
Mr Cable also emphasised that a hung parliament would not be bad for the economy, despite the fact that fears of such a possibility led to a sudden fall in the pound last week.
