More than 2.7 million migrants who wished to return home have been stranded abroad because of restrictions put in place to fight the coronavirus pandemic, the United Nations said.

The world needs to urgently step up cooperation to allow people to return in a safe manner despite the coronavirus constraints, said the UN's International Organisation for Migration.

The IOM warned in a report that border closures and travel bans had left large numbers of migrants stranded, AFP reported.

It defined stranded migrants as people outside their country of habitual residence who wanted to return home but were being prevented by restrictions related to the pandemic.