LONDON (Reuters) - Britain unveiled its planned residency rules for European Union citizens living in the United Kingdom after Brexit on Thursday, promising an “easy” system that would work in the favour of those wanting to stay.

The issue of what would happen to the more than 3 million EU citizens currently living in Britain was one of the most contentious aspects of divorce talks before a withdrawal treaty was agreed in principle between London and Brussels in March.

Home Secretary Sajid Javid said the proposed EU Settlement Scheme would be a “simple and straightforward” process, designed to ensure that EU citizens could remain in the country indefinitely.

“Throughout, we will be looking to grant, not for reasons to refuse,” he added in a statement.

Under the scheme, EU citizens who have lived continuously in Britain for five years would be granted settled status, giving them the same rights to work, study and access benefits and services as they currently do.

The scheme would also apply to their close family members, such as spouses, children, parents and grandchildren.

Those living in the UK before Dec. 31, 2020, but who had not met the residency criteria, would be granted pre-settled status until they met the five-year test.

Home Office officials said the scheme, which will be phased in later this year and run until June 2021, was designed not to be burdensome.

“We want to make it as easy as possible for EU citizens and their family members in the UK to secure their rights,” the Home Office’s Statement of Intent said.

Applicants need only to prove their identity, residency in the UK and not to be a serious criminal, with help available to try to ensure they got a positive outcome. Some 1,500 staff will work on the project which will operate online or via smartphone app, although currently unavailable to Apple users.

Each application will cost 65 pounds, or 32.50 pounds for a child, with every individual needing to apply. For those who already hold a valid permanent residence or have indefinite leave to remain, it will be free.

However, Maike Bohn, from the3million group which campaigns on behalf of EU citizens living in the UK, told BBC TV they wanted further reassurances.

“After two years of being left in limbo, we don’t take things on trust - we want legally binding guarantees that this cannot be changed by future ministers or governments,” she said. “Only then will we feel we can sleep at night and be assured that we will all stay and live our lives as we have been.”