Theresa May's government will reveal its official position on Brexit transition this morning.

Britain is set to concede that EU migrants who arrive during transition should have same rights to freedom of movement as those who arrived before.

The UK government will also demand protections against new EU rules and regulations.

Brexit Secretary David Davis will announce the guidelines to Parliament later today.

LONDON — The UK government is set to announce a major climb down on the free movement of EU migrants after Brexit when it sets out its official negotiating position on the transition period on Wednesday.

Brexit Secretary David Davis will release a statement to Parliament today outlining the UK government's official response to the European Union's negotiating guidelines for transition.

The UK government sent its official response to the European Commission and permanent representatives of the EU27 on Tuesday ahead of publication this morning, a senior Brussels source told Business Insider.

In its response, Theresa May's government has chosen not to explicitly reject the EU's demand that all migrants who arrive in Britain during transition must be given the same rights free movement rights as those who arrived beforehand, Politico reports.

This would represent a significant climbdown from May, who earlier this month insisted that EU citizens who arrive during the transition period will be treated differently to those who arrived before Brexit day in March, 2019.

The Home Affairs committee warned May last week that creating a two-tier immigration system in time for Brexit day is not "feasible" because the department is starved of time, staff and resources.

A Whitehall source insisted the government was not backing down on the free movement issue, however, telling Politico: "We are not conceding it — but we are also not putting a roadblock in the way at the outset."

The UK government is also set to demand a mechanism for protecting Britain from any "harm" brought about new rules and regulations implemented by the EU during transition (or "implementation period" as it's also known.)

The guidelines, which are expected to be made public at around 10:00 (GMT), will likely annoy the Conservative Party's most staunch Brexiteers.

Over 60 of them have signed a letter addressed to May's Cabinet laying out a list of demands for their vision of Brexit.

The letter, signed by Tory MPs including Jacob-Rees Mogg, Priti Patel, former leader Iain Duncan-Smith, was made public on the same day the UK government submitted its transition negotiating position to Brussels.

In it, Brexiteer MPs demand Britain diverges from EU regulations and is able to sign its own free trade deals after March 2019. This will be difficult to square with May's intention on keeping Britain in the customs union and single market during the 20-month transition. Being in the customs union prohibits you from signing trade deals with other countries.

Conservative MP Nicky Morgan described the letter as a "ransom note," telling The Guardian: "This isn’t a letter, it is a ransom note. The ERG clearly think they have the prime minister as their hostage."

Earlier on Tuesday, Business Insider reported that the European Parliament is planning to call for Britain to have the option of an "association agreement" with the EU after Brexit, which could allow it "privileged" access to the single market and membership of EU agencies. The pound climbed 0.5% against the Euro following the news.