It would be "undemocratic" for David Cameron or Ed Miliband to try and form a minority government after the next election, Nick Clegg has said.
The Lib Dem leader said "one of the worst things for the country after the general election next year would be a Conservative only or a Labour only government".
Speaking on his weekly LBC Radio show on Thursday morning, Clegg said voters should aim to elect another coalition government that included the Lib Dems.
"If you want both to help secure the recovery and do it as fairly as you can, it's best to have Lib Dems round the cabinet table," he said.
It was recently reported that Cameron was considering ruling out forming a second coalition after the 2015 election - even if he fails to secure an overall majority. Miliband has also been urged to shun the idea of forming a government with the Lib Dems in the event of another hung parliament.
However the deputy prime minister said any attempt by either of the big parties to try and govern as a minority administration would not be acceptable.
He told a caller: "I would warn you against the hubris of somehow suggesting the two other parties, if they don't get a majority, can nonetheless dictate to the rest of the country how the country is governed.
"In a democracy if you don't secure a majority for yourself in parliament, you don't have the right to simply decide you are going to govern the country nonetheless."
Clegg said there should be no return to the "tweedle dee tweedle dum politics of the past" of two party rule as that was "rather undemocratic".
Minority government's in Britain are rare. However John Major effectively ran one from 1996 until 1997 after his initial majority won in 1992 was whittled away.