BUDAPEST, Hungary (AP) — The Hungarian government proposed constitutional amendments and a new law Tuesday that are intended to prevent Hungary "from becoming an immigrant country" by further tightening its policies on accepting refugees and asylum-seekers.

The law submitted to parliament would make it a criminal offense punishable by up to a year in prison to promote or facilitate "illegal migration." Dubbed "Stop Soros" by the government, it partly targets civic groups, some supported by Hungarian-American financier George Soros, which offer legal and other aid to asylum-seekers.

The Hungarian Helsinki Committee, one of the groups most vilified by Prime Minister Viktor Orban's anti-immigration government, said its activities were lawful and called the proposal "unacceptable in a democratic state."

The bill "threatens to lock up and imprison those who behave legally in the defense of Hungary's human rights obligations," the group said.

The constitutional amendments put forward add language saying that "foreign populations cannot be settled in Hungary" and would place additional limits on eligibility for asylum.

For example, people who entered Hungary from a country where they were not persecuted or threatened with persecution would be ineligible.

Since most asylum-seekers from the Middle East and Asia reach Hungary from Serbia, they would be unlikely to meet the new requirement.

The United Nations refugee agency called on the government to withdraw the legislation.

"Seeking asylum is a fundamental human right. It is not a crime," Pascale Moreau, director of the UNHCR's Europe office, said. "We are particularly concerned that the government is targeting those who, in a purely humanitarian role, help people who are seeking asylum."

Orban's Fidesz party won a two-thirds majority in an April election, giving it the freedom to modify the Hungarian Constitution unchallenged. Orban, who won his third consecutive term and fourth overall, campaigned almost exclusively on fighting immigration, vowing to defend Hungary's Christian culture from immigrants who are predominantly Muslims.

Hungary built razor-wire fences on its southern borders with Serbia and Croatia in 2015 after some 400,000 people passed through the country on their way to western destinations like Germany and the Netherlands.

In the past year, the government has conducted repeated ad campaigns against Soros, accusing him of supporting indiscriminate migration to Europe.

Speaking Tuesday in Paris, Soros again rejected the Hungarian government's charges.

"Viktor Orban based his re-election campaign on falsely accusing me of planning to flood Europe, Hungary included, with Muslim refugees," Soros said at a meeting of the European Council On Foreign Relations. "He is now posing as the defender of his version of a Christian Europe that is challenging the values on which the European Union was founded."