Prime Minister Boris Johnson appointed former Brexit negotiator David Frost to his cabinet, putting him in charge of relations with the European Union and maximizing the opportunities resulting from the U.K.’s departure.

Frost, who negotiated the U.K.’s trade deal with the EU, will be a minister of state in the Cabinet Office, Johnson’s office said in an emailed statement on Wednesday. His responsibilities will include working on domestic reform and leading the committee that manages Britain’s post-Brexit ties with the bloc.

Johnson had already picked Frost to be his representative for Brexit and international policy, but his elevation to the cabinet gives him a place at the heart of government.

Frost said this month the U.K.’s relationship with the EU had been “more than bumpy” since Brexit, following disputes over vaccine supplies and disruption to trade. He now faces the challenge of smoothing those ties.

Britain and the EU are trying to resolve interruptions to goods flowing between mainland Britain and Northern Ireland, with Johnson’s government calling for grace periods covering trade to be extended. Other issues affecting U.K.-EU ties, such as access to the bloc for financial services from the City of London, remain unresolved.

Frost has also been charged with identifying domestic reforms that Britain can make now that it has left the European Union. The ability for the U.K. to set its own rules free from the shackles of Brussels bureaucracy was touted as one of the major benefits of Brexit in the 2016 referendum. So far, the U.K. government has done little to specify areas where it wishes to depart from EU rules.

A former diplomat, Frost used to run the Scotch Whisky Association and worked as a special adviser to Johnson when he was foreign secretary in 2016. After helping to negotiate the U.K.’s departure from the bloc, he took charge of the Brexit trade negotiations in Jan. 2020, which concluded with the free-trade agreement signed on Christmas Eve.