The U.K. should not have to pay to have a customs union during an interim period after leaving the European Union (EU), Brexit Secretary David Davis said on Tuesday.

Britain has proposed a temporary customs union with the EU for at least three years after Brexit in order to allow the “freest and most frictionless possible trade” with the rest of Europe.

Every country inside the EU currently imposes tariffs on imports from abroad. However, countries in the customs union do not impose taxes on each other’s goods.

When asked on ITV whether the U.K. would need to pay to remain in the EU’s customs union temporarily, Davis replied, “No I don’t think (so). Well, what happens in that interim period you have to leave me to negotiate.”

Businesses have urged Westminster to provide clarity since the government said it planned to leave the customs union as part of Brexit. The customs union document is the first of a series of reports to be published by Britain’s government.

Finance Minister Philip Hammond and Trade Secretary Liam Fox confirmed Britain would exit the EU’s customs union in a joint article over the weekend.

In response to the article, Shadow Brexit Secretary Keir Starmer said the proposals were “incoherent and inadequate” and argued the article had been designed to cover up an ongoing rift within the cabinet.