Royal assent is the final stage in the legislative process, and effectively rubber stamps the decision taken by parliament earlier this week to approve the bill after a long battle between the government and opponents of the plan.
The Royal Assent was announced in the House of Lords on Thursday, meaning the Safety of Rwanda (Asylum and Immigration) Bill will now become law, Reuters reported.
Parliament approved the legislation in the early hours of Tuesday morning. On Monday, Sunak said he expected the first flights to Rwanda to take off in 10 to 12 weeks after it was passed.