Czech Republic's President Milos Zeman prepares for the opening session of the Asia-Europe Meeting (ASEM) summit in Ulaanbaatar, Mongolia, July 15, 2016. REUTERS/Damir Sagolj

PRAGUE (Reuters) - Czech President Milos Zeman blocked a bill limiting politicians’ business interests, his office said on Monday, returning to parliament a law that would clip the wings of billionaire Finance Minister Andrej Babis if it came into effect.

Lawmakers are likely to try to overrule the president and need 101 votes in the 200-seat lower house to do so. The bill received 125 votes when approved last month.

Babis, whose ANO party is seen as the frontrunner to win parliamentary elections due by October 2017, has pledged to fight the law, which has been pushed by opponents including from within the three-party center-left ruling coalition.

The ‘conflict of interest’ law prevents ministers from accumulating media, business and political power. It would prohibit cabinet members from owning media firms and disallow companies of which ministers own more than 25 percent from accessing public contracts, subsidies and investment aid.

Babis is the second-richest Czech and the country’s largest private employer. His Agrofert group and other assets include over 250 companies from chemicals and food producers to media, forestry firms and fertility clinics, with over 30,000 workers.

Zeman had at first said he would not stand in the way of the new law but, after studying it, decided to block it because it was in conflict with the constitution and breached the principle of open competition between political parties, his office said.

Zeman has expressed support for Babis, whose ANO holds a double-digit poll lead over Prime Minister Bohuslav Sobotka’s Social Democrats.

Only Babis’s party and several independents opposed the conflict of interest bill during a vote last month.