Downing St has talked up the prospect of more intergovernmental co-operation in securing trade deals post-Brexit after the possibility of Theresa May being accompanied by Nicola Sturgeon in future investment missions was raised.

Earlier this week, David Mundell spoke enthusiastically about a “combined approach” to future trade missions, which could in theory see the Prime Minister and First Minister joining forces to get the best deals for the UK and Scotland.

Appearing before the Commons Scottish Affairs Committee, the Scottish Secretary told MPs he would welcome a move to more joint trade delegations as this would produce better value for taxpayers.

On occasions, UK and Scottish Government representatives have visited the same country but separately.

Mr Mundell told the committee: “I am very open and conducive to working together. There is continued scope for closer working. I’m sure that’s what business and industry bodies want.”

Later, when quizzed about the possibility of the PM and FM going on joint trade missions, he added: "I see no reason why that shouldn't happen. Businesses shouldn't have to choose whether they work with the UK Government or the Scottish Government. I see no impediment to that...Businesses would welcome that combined approach."

The PM’s spokesman was asked if Mrs May supported the idea of going on future trade missions accompanied by Ms Sturgeon and replied: “The PM’s deal will provide that opportunity for all parts of the UK to negotiate ambitious trade deals around the world and you have seen the clear message from Scottish businesses; they believe there are opportunities they can take advantage of if MPs support this deal.

“Scotland has some wonderful and iconic products and there will be an opportunity to sell them into new markets if we are able to get this deal through Parliament,” he added.

George Hollingbery, the International Trade Minister, also signalled that a new intergovernmental concordat, setting out Whitehall’s proposals on greater collaboration with the devolved administrations on future trade deals, would be published later this week.