Czech Prime Minister Andrej Babis won a general election on Saturday but will struggle to put together a parliamentary majority, meaning any new government could be weeks or even months away.

Preliminary results showed the populist billionaire's ANO party came first with 28 percent of the vote, despite widespread accusations of financial impropriety and just a week after he was named in the Pandora Papers investigation.

The Together alliance of the right-wing Civic Democrats, the centre-right TOP 09 and the centrist Christian Democrats came in second with 26 percent with just over 80 percent of the votes counted.

A grouping of the anti-establishment Pirate Party with the Mayors and Independents (STAN) movement scored 15 percent.

The two alliances would be able to form a majority in the 200-seat parliament, garnering 103 seats together to ANO's 75, according to a projection by Czech TV.

A potential partner for ANO could be the far-right, anti-Muslim Freedom and Direct Democracy (SPD) movement led by Tokyo-born entrepreneur Tomio Okamura which scored 10 percent.

With most of the almost all ballots counted, turnout had reached nearly 65 percent, up from 60.84 percent in the previous general election in 2017.

The 67-year-old Babis, a food, chemicals and media mogul, is facing police charges over alleged EU subsidy fraud and the bloc's dismay over his conflict of interest as a businessman and a politician.

Last weekend, the Pandora Papers investigation showed he had used money from his offshore firms to finance the purchase of property in southern France in 2009, including a chateau.

He has denied any wrongdoing and slammed the allegations as a smear campaign.

The Czech economy, heavily dependent on car production and exports to the eurozone which the EU member of 10.7 million is yet to join, is on the mend after the Covid-19 lockdowns.

But the pandemic and increases in pensions and public sector wages, recently approved by Babis's cabinet, have made the public finance gap soar.

Babis currently leads a minority government with the left-wing Social Democrats, which was until recently tacitly backed by the Communist Party that ruled the former totalitarian Czechoslovakia from 1948 to 1989.

But The Communists were ousted from parliament at the polls for the first time since World War II, scoring less than four percent according to the preliminary results, thus failing to meet the five-percent threshold for any party to enter parliament.

It will be up to the pro-Russian President Milos Zeman, Babis's old ally, to tap the new prime minister.

"He will do his best to keep ANO in power," said Josef Mlejnek, an analyst at Charles University in Prague.

But Zeman is grappling with health problems that have confined him to his residence for the vote as local media speculate he may struggle to even nominate the prime minister.

The "Pandora Papers" investigation involving some 600 journalists from media including The Washington Post, the BBC and The Guardian is based on a leak of some 11.9 million documents from 14 financial services companies around the world.