Angela Merkel has for the first time signalled that there may be some leeway on negotiating the free movement of people with Britain post-Brexit, in exchange for upholding tariff-free trade between Britain and the European Union.

Making it clear that the European Union (EU) would not divide the so-called ‘four freedoms’ – the movement of capital, goods, people and services – in order to allow Britain tariff-free access while ending immigration, the German Chancellor nonetheless conceded there could be discussions on the “framework of the free movement of people”, the International Business Times has reported.

Speaking at a meeting of Germany’s BDA employers association on Tuesday, Merkel said: “Were we to make an exception for the free movement of people with Britain, this would mean we would endanger principles of the whole internal market in the European Union, because everyone else will then want these exceptions.”

However, on the finer detail of defining the free movement of people, she said: “I personally am of the view that we will have to discuss further with the [European] commission when this freedom of movement applies from.”

As an example, she raised the scenario of those who travel from Eastern to Western Europe to work for only a short period of time, yet are eligible to claim lifelong welfare benefits. “Then I see a question about which we must talk again,” she said.

“Free movement applies to me in the sense that the employee himself earns the money he needs for himself and his family in the other member state.

“The question of when lifelong guarantees come into effect according to the social standard of the host country must certainly be taken into consideration.”

Merkel’s comments came as Foreign Secretary Boris Johnson dismissed the idea that freedom of movement is central to the EU project.

“Everybody now has it in their head that every human being has some fundamental God-given right to move wherever they want. It’s not true. That was never the case. That was never a founding principle of the EU. Total myth,” he told a Czech newspaper.

Johnson also confirmed that the UK is likely to leave the customs union post-Brexit. Insisting that there will be a “dynamic trade relationship” between the UK and the EU he said: “We will take back control of our borders, but we remain an open and welcoming society.”

He continued: “We probably will have to come out of the customs union, but that’s a question I am sure will be discussed.”