David Lammy must “engage with China as it really is under the leadership of Xi Jinping” and raise human rights concerns during his trip to the country, UK parliamentarians who have been hit with sanctions by Beijing have said. The foreign secretary is expected to hold high-level meetings in China this week. The visit forms part of an effort by Labour to improve relations with China after they deteriorated under successive Conservative governments. Rachel Reeves, the chancellor, plans to travel to the country next year and restart high-level economic dialogue. The rapprochement is controversial because of human rights and security concerns about China, including its treatment of the Uyghur Muslim minority in Xinjiang and crackdown on democratic freedoms in Hong Kong. In a letter to Lammy on Tuesday, the group of parliamentarians wrote that “Beijing is testing the UK’s resolve [and] seeking to establish new parameters for engagement”. Beijing imposed sanctions on the group, which includes the Labour peer Helena Kennedy, in 2021 for criticising its human rights record in Xinjiang. In their letter, the parliamentarians urge Lammy to raise the case of political prisoners in Hong Kong, including the British citizen Jimmy Lai, and the “heinous treatment” of the Uyghur community. They call on the foreign secretary to express “deep concern” about China’s “unilateral alteration of the status quo” in Taiwan. The Chinese military held drills around Taiwan on Monday in what it called a “stern warning” against those seeking “independence” for the self-ruled island. The Guardian reported last week that the Foreign Office had asked that a visit to the UK parliament by Tsai Ing-wen, the former Taiwanese president, be delayed so as not to anger China before Lammy’s trip. Tsai is travelling to Prague and Brussels on her first international tour since leaving office. The letter warns that “the projected $10tn impact of a conflict over Taiwan to the global economy is intolerable and would be catastrophic for China’s standing in the world”. Taiwan, which has never been ruled by the People’s Republic of China, has grown increasingly opposed to Beijing’s claims of sovereignty over it. There are fears China will eventually try to annex the island by force. Signatories of the letter include the former Tory leader Iain Duncan Smith, the former security minister Tom Tugendhat and the former health minister Neil O’Brien. “We must engage with China as it really is under the leadership of Xi Jinping, not as we all hoped it would become after accession to the World Trade Organization,” they wrote. “Our own political environment means that the temptation to prioritise short-term economic advantage over UK resilience and values is strong, but will only disadvantage the UK in the long run.” The letter urges Lammy to underline that the UK’s concerns are not a product of alignment with US foreign policy but “a result of non-negotiable values which rest at the heart of the UK national interest”. The last foreign secretary to visit China was James Cleverly in August 2023. Earlier this year the UK and US governments accused Chinese state-backed hackers of a years-long cyber-attack targeting politicians, journalists and businesses. In its manifesto, Labour pledged to conduct a Whitehall audit of the UK-China relationship. In the past, Labour has also committed to taking steps to recognise China’s treatment of its Uyghur minority as genocide. Lady Kennedy and Duncan Smith are UK co-chairs of the Inter-Parliamentary Alliance on China, which is strongly critical of Beijing. A FCDO Spokesperson said: “This government will take a consistent, long term and strategic approach to managing the UK’s relations with China, rooted in UK and global interests. We will co-operate where we can, compete where we need to, and challenge where we must. “It is only right that we engage pragmatically with China where there are clear UK and global interests. That includes on areas where we agree and more importantly where we disagree, as the foreign ssecretary did during his meeting with Wang Yi at ASEAN. “Foreign secretary travel will be confirmed in the usual way.”