Two United Nations (UN) top officials on Tuesday called on the UK to reconsider its plan to transfer asylum seekers to Rwanda, warning the move would have a harmful impact on human rights and refugee protection.

In a joint statement, Filippo Grandi, the UN High Commissioner for Refugees, and Volker Turk, the UN High Commissioner for Human Rights, called on the UK to instead take practical measures to address irregular flows of migrants and refugees.

"The new legislation marks a further step away from the UK's long tradition of providing refuge to those in need, in breach of the Refugee Convention," said Grandi.

Turk, who has criticised the plan before, said that the legislation "seriously hinders the rule of law in the UK and sets a perilous precedent globally".

British Prime Minister Rishi Sunak promised on Monday to start sending asylum seekers to Rwanda within 10 to 12 weeks as the upper house of parliament passed legislation that had been delayed for weeks by attempts to alter the plan.

Other countries are considering tough measures to stem illegal migration, with Italy planning to build reception camps in Albania for thousands of migrants arriving by sea.