The committee said it was calling on the British government to withdraw the bill or repeal it if it passed.
The United Nations Human Rights Committee urged Britain on Thursday to abandon a contentious bill to deport refugees to Rwanda, which could become law next month.
In its review of the United Kingdom, the committee said it regretted the arrangements made with some with third countries, particularly Rwanda, to transfer asylum seekers, as well as "efforts to adopt the Safety of Rwanda (Asylum and Immigration) Bill despite the UK Supreme Court's ruling that the arrangement would not be compliant with international law".
The committee said it was calling on the British government to withdraw the bill or repeal it if it passed.
Prime Minister Rishi Sunak's Conservative government wants to relocate thousands of asylum seekers who arrive in Britain on small, inflatable boats each year to live in Rwanda, but legal challenges have so far prevented anyone being sent to the country.
The government suffered a setback to its Rwanda plan - which it hopes would also act as a deterrent to people trying to cross in small boats - when the UK's Supreme Court ruled last year the policy was unlawful because there was risk that people sent there could be sent back to their country of origin and their safety jeopardised.
To overcome the court's objections, Sunak's government is hoping to pass a bill that declares Rwanda a safe country for asylum seekers. The legislation will come up for debate again in parliament again on April 15.