Sir Keir Starmer has said he told Xi Jinping he wanted “respectful” relations with Beijing as he became the first prime minister to meet the Chinese president since 2018.

The Prime Minister raised the case of detained pro-democracy activist Jimmy Lai in a sign he was prepared to challenge China over human rights abuses, but he also signalled a desire for greater business co-operation.

Sir Keir also suggested a full UK-China meeting in London or Beijing as part of his desire for “consistent, durable, respectful” ties between the two countries.

Sir Keir Starmer and Xi Jinping met in Rio de Janeiro (Stefan Rousseau/PA)

The pair met in Brazil, where both leaders are attending the G20 summit.

Sir Keir said a “strong UK-China relationship is important for both of our countries” and for the “broader international community”.

The UK-China relationship has deteriorated in recent years, with concerns over security, human rights and the sanctioning of Westminster parliamentarians souring ties with Beijing.

Despite the renewed engagement by the Labour administration, the relationship is still a long way from the “golden era” sought by the Conservatives under David Cameron and Theresa May.

The Prime Minister told the Chinese leader: “We want our relations to be consistent, durable, respectful, as we have agreed, avoid surprises where possible.”

He added: “The UK will be a predictable, consistent, sovereign actor committed to the rule of law.”

The UK and Chinese leaders met at the Sheraton Grand Hotel in Rio (Stefan Rousseau/PA)

Sir Keir’s meeting followed Foreign Secretary David Lammy’s visit to Beijing in October for talks with counterpart Wang Yi.

The Prime Minister told Mr Xi: “I’m very pleased that my Foreign Secretary and foreign minister Wang met recently to discuss respective concerns including on human rights and parliamentary sanctions, Taiwan, the South China Sea and our shared interest in Hong Kong.

“We are concerned by reports of Jimmy Lai’s deterioration.”

Sir Keir also said he was keen for Chancellor Rachel Reeves to meet vice premier He Lifeng “to explore more investment projects and a more level playing field to help our businesses”.

A No 10 spokeswoman told reporters: “We’ve consistently said when it comes to China that it is important to engage seriously and pragmatically, and that involves challenging (the Chinese) where necessary.”

She added: “The Prime Minister believes that it’s as important, as a serious government, to engage with China given the size of the economy and its position on the world stage.

“His priority is on pursuing pragmatic and serious diplomatic relationships.”