Jeremy Hunt has called on Boris Johnson to match 10 key campaign pledges in Scotland to boost the chances of a Conservative victory at the next Holyrood election.
The Foreign Secretary said committing to the policies – which focus on fishing, the armed services, the economy and the Union – would give Scottish Conservative leader Ruth Davidson the best chance of winning in 2021.
He urged his rival in the Conservative leadership race which determines the next prime minister to back the 10-point plan in a “union against Nicola Sturgeon”.
The pledges include removing the UK from the Common Fisheries Policy by December 2020 and appointing a fishing minister throughout Brexit.
Ensuring servicemen and women are not disadvantaged by the Scottish tax differential and “securing the future” of RAF Lossiemouth and Kinloss Barracks are also on the list.
Further promises include setting up UK investment hubs, expanding city and regional growth deals, reviewing spirit duty and investing in more effective promotion of the Union in Scotland.
He also plans to build an immigration system suited to Scottish agriculture, although he has stressed this would not include regional differentiation.
Mr Johnson has already matched the pledge to retain the Barnett formula, which governs how public spending is allocated across the UK.
Mr Hunt said: “The best way to protect the Union is a Ruth Davidson victory in the 2021 election.
“We should work with the Scottish Government on everything except independence but we must acknowledge that Nicola Sturgeon has no intention of working constructively with the UK Government over the long term.
“Whoever becomes prime minister must be ready to take the fight to the SNP and send them packing in 2021.
“So I’m calling for a union against Nicola Sturgeon, and for Boris Johnson to match my pledges to back Scottish businesses, our armed forces and our fishermen.”
Ms Davidson is backing Mr Hunt in the campaign, after her previous candidates Sajid Javid and Michael Gove were eliminated from the race.