EU nationals arriving in the UK before the end of next year could be permitted to stay for three years in the event of the UK leaving the EU without a deal.
The government is expected to announce later that a temporary Leave to Remain scheme would replace free movement.
This would allow EU nationals, who arrive before the end of 2020 and register with the EU settlement scheme, to stay until December 2023.
The government had hoped to end free movement under a no-deal Brexit.
Free movement of EU citizens will not automatically end as a result of a no-deal Brexit, because EU law will continue to apply until its legal foundation is repealed.
Last month, the UK government announced EU free movement rules would end immediately if there