The US president's comments come as Sir Keir Starmer arrives in Shanghai on the third day of his visit to China.

Donald Trump has warned Sir Keir Starmer that cosying up to China will be “very dangerous”. The US president issued the warning as the Prime Minister concluded his second day of his visit to China. On Thursday, Sir Keir met Xi Jinping, the president of China, and said it was time for a “more sophisticated” relationship between the countries.

British Prime Minister Keir Starmer has arrived in the Chinese financial center of Shanghai in his bid to boost business opportunities for U.K. firms in the world’s second-largest economy, just hours after President Donald Trump signaled a possible opposition to any deal between Beijing and London.

Leaders from Canada, the United Kingdom, Finland and other countries have recently visited China, while more are planning to go.

Executives from Airbus, AstraZeneca and HSBC are joining Prime Minister Keir Starmer on a rare China visit, highlighting the business focus of the trip amid strained global trade relations.

The leaders of Britain and China have called for a “comprehensive strategic partnership” to deepen ties at a time of global uncertainty.

When Sir Keir Starmer landed in China on Wednesday, his first stop was at Yi Zuo Yi Wang – a popular restaurant famous for cooking hallucinogenic mushrooms.

The prime minister seeks to strengthen ties with China but faces fierce criticism from opponents at home.