After three days of talks with senior politicians, King Albert II tasked a former premier with sounding out political parties to see who might be the best candidate to end the power-sharing tussle, with Belgium mired in economic woe.

"The king has accepted the resignation of the government and ordered it to carry out day-to-day business," said a short statement from the royal palace.

It gave no indication of who might replace Leterme, who resigned Friday following allegations that his aides had sought to influence a court ruling linked to the break-up of Fortis, one of the kingdom's biggest banks.

Then, in a similar communique a few hours later, the palace said: "The king has received Mr Wilfried Martens for an audience this evening at Laeken Chateau."

"The king has charged him with an exploratory mission to try to find a rapid solution to the current political crisis. Mr Wilfried Martens has accepted this mission," it said.

Martens, 72, is like Leterme a Flemish Christian Democrat and served as prime minister almost without interruption from 1979 to 1992.

But the fact that he was named suggests the king is struggling to find someone with the political clout necessary to overcome Belgium's deep linguistic divisions, and that considerable time might yet be needed.

Another former premier, Martens' successor Jean-Luc Dehaene, has emerged a favourite, with his photograph on the front page of a number of newspapers Monday.

In a separate statement, Leterme thanked his team and said he had spared no effort in trying to overcome the power-sharing crisis that has dogged him since he won the elections in June 2007.

The 48-year-old Christian Democrat never managed to ease differences between Belgium's French-speaking community and Dutch-speakers in the north, who insist that any new cabinet should start handing over powers to the three regions that also include the Brussels area.