London - Britain has begun a study of the "costs and benefits" of EU immigration that will only be completed by September 2018 - just a few months before it is planning to leave the bloc.
Home Secretary Amber Rudd said the study would consider the regional distribution of EU migration, which industries are most reliant on it and the role of temporary and seasonal workers in the economy.
"We will ensure we continue to attract those who benefit us economically, socially and culturally.
"But, at the same time, our new immigration system will continue to give us control of the volume of people coming here," she wrote in the Financial Times.
Rudd supported the campaign for Britain to stay in the European Union and, while she now supports Brexit, her position is seen as more moderate than other cabinet members who want a clean break from the EU.
She said she wanted to reassure businesses and EU nationals "that we will ensure there is no 'cliff edge' once we leave the bloc".
Josh Hardie, deputy head of the Confederation of British Industry (CBI), welcomed the study as a "sensible first step" but opposition parties questioned why it had not been carried out before.
"The NHS (National Health Service), businesses and universities that depend on European citizens need answers now, not in another 14 months' time," said Ed Davey, home affairs spokesman for the Liberal Democrats.
The government has outlined proposals for the status of 3.2 million EU nationals already living in Britain but has not said what new immigration rules it wants once it is out of the bloc.
High rates of immigration from other parts of the EU - around 250,000 people a year - were one of the key drivers behind the victorious campaign for leaving the union in last year's referendum.
EU immigration has fallen by around a quarter since the vote, leaving some sectors such as the health service struggling to fill vacancies.
The EU's chief Brexit negotiator Michel Barnier has indicated that a divorce deal should be in place by October 2018 to allow time for ratification before the scheduled departure date of March 2019.
Media reports have highlighted divisions in the government, with some moderates indicating that free movement of people could continue during a transition period of up to four years even after Brexit.
But junior immigration minister Brandon Lewis told BBC radio that free movement would end when Britain leaves in 2019.
He said that ahead of that date, the government would put forward an immigration bill next year.
"There will be a new immigration system in place from the spring of 2019," he said.