Viktor Orban said on Monday the main task of his new government will be to preserve Hungary's security and Christian culture, sticking to his nationalist policy to keep out migrants and fend off what he calls foreign meddling.

The right-wing prime minister, 54, was re-elected for a third straight term in an election last month after a strong anti-immigration message landed him a landslide victory.

One of the most vociferous opponents of immigration into Europe by mainly Muslim people fleeing war and poverty in the Middle East and Africa, Orban's campaign — helped by his party's media dominance — resonated with large swaths of the electorate, particularly in rural areas.

His Fidesz party now holds 133 of 199 seats in the new parliament that will enable Fidesz to pass any laws, even those that require the support of two-thirds of the votes.

"The main task of the new government will be to preserve Hungary's security and Christian culture," Orban told a news conference after he was asked by the president to form a new government.

Parliament will hold its first session on Tuesday where Orban will be officially elected prime minister again. In a radio interview on Friday, Orban said his government was building a "Christian democracy."

"We are working on building an old-school Christian democracy, rooted in European traditions ... we believe in the importance of the nation, and in Hungary we do not want to yield ground to any supranational business or political empire," Orban said.

Soros attacks

Orban has accused non-governmental organisations (NGOs) funded by Budapest-born billionaire George Soros of political meddling and actively supporting migration.

He said any organization involved in the migration issue would have to seek clearance from national security authorities.

One of the first new laws expected to be passed by parliament is a "Stop Soros" bill, which would impose a 25 per cent tax on foreign donations to NGOs that back migration.

Soros has said the attacks against him were "lies and distortions" and were designed to create a false external enemy.

Another term for Orban could also have implications for Soros's Central European University, a graduate school which is considered by the government a foreign institution. Michael Ignatieff, the school's rector and former Liberal Party leader in Canada, told Reuters last week the school's Vienna campus would soon be able to accommodate more students if necessary.