ONE of Nicola Sturgeon’s Brexit advisers has left the Scottish Government’s council on Europe to take up a similar job working for Boris Johnson.

David Frost will also step down from his role as chief executive of the Scottish Whisky Association (SWA) after being appointed as foreign affairs special adviser to the UK Foreign Secretary.

Mr Frost, who is believed to have backed the Remain campaign, was formerly a career diplomat for 25 years, including as Britain’s ambassador to Denmark and in the then Department of Business, Innovation and Skills (BIS).

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From November 4 he will advise Mr Johnson, who backed leaving the European Union in June’s referendum.

Mr Frost said: “I have thoroughly enjoyed my time as chief executive and I want to thank SWA members and my team for their support.

“Scotch Whisky is a wonderful industry to represent, vital to Scotland and to Britain, operating on a global scale, and held in affection by so many around the world.

“I leave the association and the industry well-placed to continue to succeed in a competitive market-place during a time of change, including Brexit.”

The SWA had previously warned that leaving the EU could result in high tariffs on whisky, while Mr Frost called on the UK Government to “bring clarity to the transition to Brexit as soon as possible”.

He added: “It is clear, however, that the uncertainties of the Brexit vote will create challenges for exporters and we continue to encourage early clarity on the likely shape of the UK’s future trading relationship with the EU and other countries.

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“We are working closely with our members and government to ensure the industry’s trade priorities are well understood, to promote open markets, and to identify opportunities to grow our exports in the future.”

The SWA also said that losing access to the EU free trade agreements (FTAs) would be one of the biggest challenges the industry could face, and that negotiators would be entering “unchartered territory”.

Mr Frost predicted that it would be extremely unlikely a fresh FTA could be agreed within a three-year timescale.

When announcing the launch of the EU advisory body, the First Minister said: “The council draws on a breadth and wealth of knowledge and experience, comprising specialists with backgrounds in business, finance, economics, European and diplomatic matters, and it will encompass a range of political and constitutional opinions.

“Members will consider the impact of proposed changes to the UK’s relationship with the EU on Scottish interests and advise Ministers throughout our negotiations on the best way to secure Scottish interests and objectives.”

A Scottish Government spokesman said: “We thank David for his work while on the Standing Council on Europe and wish him well in his new role.”

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Deputy chief executive Julie Hesketh-Laird will stand-in until a replacement for Mr Frost can be found.

Ms Hesketh-Laird joined the SWA in 2005 as director of operational and technical affairs and was additionally appointed deputy chief executive in December 2014.

She said: “We are sorry to see David leaving the SWA, but wish him well in his exciting future role. I look forward to leading the Association for this transitional period and believe we have a great team to deal with whatever challenges face us.”

SWA chairman Pierre Pringuet, vice-president of Pernod Ricard, added: “We have very much valued his leadership and I am confident he leaves the SWA in a good position to face the future.”