The UK will look to pursue trade deals with countries around the world despite potentially being bound by European Union rules for around two years after Brexit, Theresa May is to tell MPs.
Delivering an update to the Commons on the recent Brussels summit, the Prime Minister will say that even though the UK is leaving the single market and customs union in March 2019 she wants "access to one another's markets" to continue "as now" during an implementation period.
According to the EU, during the transition period the UK would have to comply with the bloc's trade policy - preventing it from agreeing its own deals with other countries.
However, May will say the UK wants to sign agreements which would come into force after the "strictly time-limited" period has ended.
"We will prepare for our future independent trade policy by negotiating - and where possible signing - trade deals with third countries, which could come into force after the conclusion of the implementation period," she will say.
May and her senior ministers will also begin the process of thrashing out the Government's plans for a post-Brexit UK-EU trade deal as Brussels indicated she may not get the "special partnership" she wants.
The Prime Minister will say there is a "shared desire" between the UK and EU for "rapid progress on an implementation period" before any UK-EU deal comes fully into effect.
The EU's negotiating position makes clear that the bloc expects the UK to observe all of its rules - including on freedom of movement - and accept the jurisdiction of the European Court of Justice (ECJ) during this time.
May will say that "we would not be in the single market or the customs union, as we will have left the European Union" but "we would propose that our access to one another's markets would continue as now".
Yet free movement rules are unlikely to continue in exactly the same way. May will say that "during this period we intend to register new arrivals from the EU as preparation for our future immigration system".
Eurosceptics on the Tory benches have already warned against accepting an implementation period which would leave the UK bound by EU laws without a say over how they are made.
A Brexit Cabinet committee meeting on Monday will potentially see a clash between ministers who favour the closest possible ties with the EU in future - requiring ongoing alignment with Brussels' regulations - and those who seek a looser arrangement giving the UK more flexibility to strike favourable deals around the world.
Foreign Secretary Boris Johnson told the Sunday Times: "What we need to do is something new and ambitious, which allows zero tariffs and frictionless trade but still gives us that important freedom to decide our own regulatory framework, our own laws and do things in a distinctive way in the future."
He said that if Britain were forced to mirror EU laws after Brexit "we would have gone from a member state to a vassal state".
May has rejected pre-existing models for a future UK-EU relationship such as Norway-style membership of the European Economic Area (EEA) or a Canadian-style free trade deal on goods.
Brexit Secretary David Davis described his vision of the deal as "Canada, plus, plus, plus" - taking in not only trade but services and cooperation in other areas.
But the EU's chief Brexit negotiator Michel Barnier told Prospect magazine: "They have to realise there won't be any cherry picking. We won't mix up the various scenarios to create a specific one and accommodate their wishes, mixing, for instance, the advantages of the Norwegian model, member of the single market, with the simple requirements of the Canadian one.
"No way. They have to face the consequences of their own decision."