The U.K.’s new trade minister said on Tuesday he was optimistic some trade barriers with the European Union can be removed, but the mechanism to arbitrate any disputes would be subject to negotiation.

The Labour Party won a July 4 election, and while it has pledged not to reopen the core pieces of Britain’s deal to leave the European Union, it is aiming for a new food and veterinary agreement to reduce border checks on animal products.

Critics say that will mean accepting oversight from the European Court of Justice (ECJ), a red flag to Brexit campaigners who see it as an infringement of British sovereignty.