Sunak faced the most serious threat to his leadership when he saw off a revolt by dozens of his lawmakers during the first parliamentary vote on the draft legislation last month.
The government won that first vote more comfortably than had been expected after about 30 Conservative members of parliament decided to abstain rather than oppose the bill.
But the rebels warned that they could vote down the legislation at later stages of the parliamentary process unless the bill was changed to make it tougher.
It will now be debated on January 16 and 17, the leader of the House of Commons Penny Mordaunt said on Tuesday, when lawmakers have their first opportunity to put forward amendments.
The British government is trying to reduce a surge in asylum-seekers who make the dangerous crossing in small boats from neighboring France to the southern coast of England.
Sunak has staked his premiership on “stopping the boats” and has vowed to push through the plan to deport migrants to Rwanda before a general election expected this year.
In November, the UK Supreme Court ruled Sunak's policy of deporting migrants to Rwanda would breach British and international human rights laws and agreements.
In response, Sunak agreed a new treaty with the East African nation and brought forward the new legislation designed to override any legal obstacles that would stop deportations.