WASHINGTON (AFP) - First lady Melania Trump's parents have become permanent US residents, their lawyer said on Wednesday (Feb 21), apparently taking advantage of a family unification programme pilloried by the President.

"I can confirm that Mrs Trump's parents are both lawfully admitted to the United States as permanent residents," lawyer Michael Wildes said in a statement.

Viktor and Amalija Knavs, like their daughter, are from Slovenia.

They appear to have taken advantage of a system that Donald Trump has dubbed "chain migration" and has promised to end.

The programme allows naturalised citizens, in this case likely the First Lady, to sponsor visas for close family members.

The news, first confirmed by the Washington Post, prompted allegations of White House hypocrisy on Wednesday.

"Almost every US family is connected to immigration programmes Trump wants to kill, including his own," said Democratic congressman Luis Gutierrez.

Trump has made a hardline stance on immigration part of his core electoral message.

He has railed against migrants from Muslim countries and Latin America.

The First Lady's office has for months ignored requests for comment on the status of Viktor and Amalija Knavs.

"The family, as they are not part of the administration, has asked that their privacy be respected so I will not comment further on this matter," said Wildes.