Secured by International Trade Secretary Liam Fox, the deal is expected to benefit Scotland, which produces around 70% of the 100,000 tonnes of seed potatoes that are exported from the UK on an annual basis. The seed potato export market is already worth an annual £90 million to the UK, with some varieties fetching up to £900 per tonne.

China is currently the largest global consumer of potatoes in the world, with it being China’s fourth staple crop after rice, corn and wheat.

International Trade Secretary Dr Liam Fox MP said: “The rapidly-growing Chinese market offers huge potential for UK farmers. According to research by Barclays, around 60% of people in China would actually pay more for a product, just because they knew it was British. With China expected to have 220 cities with a population of more than a million by 2030, that is a huge market which UK potato farmers will now be able to make the most of​.

“I’m delighted that this latest deal is set to boost our £67.5bn trading relationship with China even further​.”

UK Government minister Lord Duncan said: “Linking the world’s largest consumer of potatoes, China, with Scotland’s exceptional potato seed is a welcome next step for the UK on a global stage​.”

Rob Burns, head of crops export trade development at the Agriculture & Horticulture Development Board (AHDB), said: “It’s a real coup to be one of the first western countries able to export seed to China and it has been achieved through a lot of hard work and the great reputation of UK seed potatoes, which are rightly renowned around the world for their high health status and high quality​.

“I expect the Chinese market will be particularly interested in processing varieties used for chips and crisps as there is a big demand for those products. AHDB’s role now will be to develop this new trading relationship through events such as large-scale trade shows, where exporters can showcase their varieties and start building business in China​.”

Rural Economy Secretary, Scotland Fergus Ewing added: “I am delighted that Scottish seed potatoes will now be enjoyed by the biggest producers in the world, the People’s Republic of China. This is welcome news for the Scottish seed potato sector and further recognition of its global renown for producing high-quality seed potatoes​.

“The signing of this trade agreement has the potential to lead to its expansion to the rest of the UK, opening up the possibility of market diversification and contributing towards further sustainable growth in the sector​.”

Earlier this year, China also lifted its longstanding BSE ban on the exports of beef from the UK​​, worth an estimated £250m in the first five years alone.