Andrej Babis, a billionaire supporter of US President Donald Trump, returned to power as Czech prime minister on Tuesday, signalling a possible end to Ukraine aid and potentially rockier ties with the European Union.

Babis's ANO movement, which won October parliamentary elections, teamed up with two eurosceptic parties to form a coalition government.

In its policy statement, the coalition said the EU had "its limits" and no right to impose decisions infringing on the sovereignty of member states.

In his campaign, Babis has also vowed to curb aid to Ukraine. The outgoing centre-right government gave humanitarian and military aid.

President Petr Pavel, who beat Babis in a 2023 presidential run-off vote, appointed the 71-year-old, who governed the EU and Nato member of 10.9 million people from 2017 to 2021.

"I promise all citizens of the Czech Republic to fight for their interests at home and abroad," said Babis, who has described himself as "Trumpist" in the past.

Throughout his political life, Babis has battled conflict of interest allegations over his roles in business and politics, drawing mass protests during his earlier term.

Thousands rallied against Babis last month on the anniversary of the 1989 Velvet Revolution that toppled communism in the former Czechoslovakia.

Slovak-born, Babis is the seventh wealthiest Czech according to Forbes magazine. He made his fortune as the owner of the sprawling food and chemicals holding Agrofert and other companies.

Pavel urged Babis to resolve the conflict of interest before he is appointed, and the new premier last week vowed to put Agrofert in the hands of an independent administrator.

He did not disclose details, sparking speculation about the move, but Pavel said he was happy with the explanation and promised to appoint him.

Babis is due to stand trial over a two-million-euro fraud. He is accused of taking a farm out of Agrofert in 2007 to make it eligible for an EU subsidy for small companies. (AFP)