Government plans for immigration after Brexit have been thrown into chaos after immigration minister Brandon Lewis contradicted earlier indications that free movement would continue after March 2019.

Insisting that Britain would no longer adhere to the free movement of people – one of the EU’s four freedoms – when it leaves the bloc in spring 2019, Mr Lewis said the UK would have a new immigration system in place in just 20 months’ time.

“There will be a new immigration system in place from the spring of 2019 and that will be outlined in the Immigration Bill that will go through Parliament next year,” he vowed.

Just hours earlier, Home Secretary Amber Rudd, his superior, said the flow of EU workers would continue for an “implementation period” after Britain formally leaves the EU, to ensure that there is “no cliff edge” for employers – a move welcomed by business leaders.

And, last Friday, Michael Gove, the Environment Secretary, said the UK is willing to allow EU citizens to enjoy free movement for a transitional period after Brexit, expected to last two years.

The impression of confusion at the heart of Government was heightened as it emerged the major report on the impact of changes to the immigration system would not be published until September 2018 – just six months before Brexit.

But Mr Lewis told BBC Radio 4’s Today programme: “Free movement of labour ends when we leave the European Union in the spring of 2019 – we’re very clear about that.”

Asked why free trade and single market access would not also end then, Mr Lewis said: “There’s a period of negotiation we’re going through with the European Union at the moment, but we’re very clear that free movement ends – it’s part of the core principles, the four key principles, of the European Union – when we leave.”

Pressed on whether it was a red line to end free movement in March 2019, he said: “It’s a simple matter of fact that the four key principles of the European Union include free movement – we won’t be a member of the European Union when we leave.”

In the interview, the immigration minister also repeatedly failed to say whether the Conservatives would achieve their manifesto pledge to bring migration down to the tens of thousands by the end of this Parliament, in 2022.

Asked several times on Radio 4 whether his department would achieve its manifesto commitment, he replied: “It’s not a straight-forward issue. We cannot control our net migration levels fully until we leave the European Union.”

In pictures: European parliament Brexit discussions Show all 12 1 /12 In pictures: European parliament Brexit discussions In pictures: European parliament Brexit discussions European commission member in charge of Brexit negotiations with Britain, French Michel Barnier listens at the President of the European Commission Jean-Claude Juncker speaking at the European Parliament in Strasbourg Getty Images In pictures: European parliament Brexit discussions Frank-Walter Steinmeier, President of the Federal Republic of Germany, delivers his speech at the European Parliament in Strasbourg EPA In pictures: European parliament Brexit discussions European Union's chief Brexit negotiator Guy Verhofstadt, President of the Group of the Alliance of Liberals and Democrats for Europe (ALDE), addresses the European Parliament during a debate on Brexit priorities and the upcomming talks on the UK's withdrawal from the EU Reuters In pictures: European parliament Brexit discussions Michel Barnier, European Chief Negotiator for Brexit reacts during a meeting at the European Parliament in Strasbourg EPA In pictures: European parliament Brexit discussions Member of the European Parliament and former leader of the anti-EU UK Independence Party (UKIP) Nigel Farage wears socks with Union Jack flag at the European Parliament in Strasbourg Getty Images In pictures: European parliament Brexit discussions Nigel Farage, United Kingdom Independence Party (UKIP) member and MEP, addresses the European Parliament during a debate on Brexit priorities and the upcoming talks on the UK's withdrawal from the EU Reuters In pictures: European parliament Brexit discussions European commission member in charge of Brexit negotiations with Britain, French Michel Barnier gestures during speeches at the European Parliament in Strasbourg Getty In pictures: European parliament Brexit discussions The President of the European Commission Jean-Claude Juncker (L) speaks with European commission member in charge of Brexit negotiations with Britain, French Michel Barnier at the European Parliament in Strasbourg Getty In pictures: European parliament Brexit discussions European Union's chief Brexit negotiator Guy Verhofstadt, President of the Group of the Alliance of Liberals and Democrats for Europe (ALDE), addresses the European Parliament during a debate on Brexit priorities and the upcomming talks on the UK's withdrawal from the EU Reuters In pictures: European parliament Brexit discussions Member of the European Parliament and former leader of the anti-EU UK Independence Party (UKIP) Nigel Farage gestures during speeches at the European Parliament in Strasbourg, eastern France, on April 5, 2017. The European Parliament will on April 5 lay down its "red lines" for negotiations over a Brexit deal, on which the assembly will have the final say in two years' time. / AFP PHOTO / Sebastien BozonSEBASTIEN BOZON/AFP/Getty Images Getty In pictures: European parliament Brexit discussions German president Frank-Walter Steinmeier delivers a speech during a plenary session at the European Parliament in Strasbourg Getty In pictures: European parliament Brexit discussions The European Parliament in Strasbourg, eastern France Getty Images

The latest statistics show that net long-term migration for EU citizens – the balance between arrivals and departures – was running at an estimated 133,000 last year, a fall of more than a quarter on 2015. But, overall international net migration, including from outside the EU, stood at 248,000 in 2016 – considerably above the Government’s target.

Diane Abbott, the Shadow Home Secretary, said: “There is far too much heat and not enough light about immigration, so any truly objective and well-informed analysis must be welcome.

“We already know that immigrants, both EU and non-EU, make a huge contribution to the economy and to wider society. They occupy both high-skilled, high-wage jobs and lower-skilled, lower-paid ones, adding value across a wide range of economic sectors. They help make the UK more internationally competitive, and sectors with staff shortages, such as the NHS, social care and agriculture, would be in serious difficulty without them.