A majority of UN states adopted on Monday a non-binding global pact to better handle migrant flows, Morocco's foreign minister said, though fewer governments joined than had previously worked on the proposal.

Moroccan foreign minister Nasser Bourita announced the decision as host of the UN conference in Marrakesh. There was no formal vote.

In July, all 193 UN members except the United States finalised the so-called Global Compact for Safe, Orderly and Regular Migration to better handle migration.

Since then, the text has come under fire from mostly right-wing European politicians who say it could increase immigration from African and Arab countries. At least six European Union members - mostly in formerly Communist Eastern Europe - have shunned the accord.

It was not immediately clear how many countries were present in Marrakesh. The UN had put the number of governments registered late on Sunday at more than 150.

The compact is a framework for cooperation and aims to reduce illegal migration, help integrate migrants and return them to their home countries.

On Sunday Chile was the latest country to pull out, while Belgian Prime Minister Charles Michel saw the biggest party in his coalition quit in a dispute over the accord.

In November, Austria's right-wing government, which holds the EU presidency, said it would also withdraw, saying the accord would blur the line between legal and illegal migration.

Australia also said in November would not sign up to the migration agreement because it would compromise its hardline immigration policy and endanger national security.