The Brexit spokesman for Britain's main opposition party has admitted his colleagues are divided over the issue, as British and European businesses sound increasingly urgent warnings about the economic damage the U.K.'s exit from the EU could cause.

The Labour Party's Keir Starmer said Wednesday that "there are very divided views" among Labour lawmakers over whether Britain should try to remain in the EU's single market after Brexit.

Instead, Labour leader Jeremy Corbyn is calling for Britain to have "full access" to the single market.

But EU leaders have repeatedly said Britain can't have the benefits of membership without the responsibilities.

Britain is due to leave the EU on March 29, 2019, and many businesses say they urgently need to know what future trade arrangements will be.