Hungary's parliament adopted Wednesday a controversial package of laws penalising NGOs that help migrants, a key proposal of the firebrand nationalist Prime Minister Viktor Orban.

Dubbed the 'Stop Soros' laws after liberal US billionaire George Soros, accused by the government of orchestrating migration to Europe, the package of legislation was voted through by 160 votes to 18.

The government says the laws are aimed at people helping undeserving migrants to acquire refugee status, for example if those persons were not in immediate danger before entering Hungary, or who entered the country illegally.

The Hungarian chapter of rights pressure group Amnesty International, which could find itself targeted under the new laws, called them "a brazen attack on people seeking safe haven from persecution and those who carry out admirable work to help them".

"It is a new low point in an intensifying crackdown on civil society and it is something we will resist every step of the way," Amnesty said in a statement.

The 'Stop Soros' laws were promised by Orban in the lead-up to a parliamentary election in April, in which Orban's ruling Fidesz party won a third consecutive term by a landslide.

The campaign was dominated by anti-migrant and anti-Soros messaging on pro-government media.