The investigation into the death of British businessman Neil Heywood must observe due process and address concerns raised about the suspicious circumstances surrounding his demise, Prime Minister David Cameron was telling a senior official of the Chinese Communist Party.
Mr Cameron was meeting Politburo member Li Changchun at No 10 to discuss efforts to deepen the UK's trade and cultural relationship with China, as well as bilateral co-operation on global issues like Iran and Syria, said Downing Street.
But the PM was also planning to raise the death of 41-year-old Mr Heywood, who died in the city of Chongqing last November.
Mr Heywood was a friend of the family of Bo Xilai, a former rising star in Chinese politics who served as local party chief in Chongqing but was suspended from the Politburo in April amid allegations of "serious discipline violations".
State media reports in China have suggested that investigations by authorities there indicate Mr Heywood was a victim of homicide.
Unconfirmed media reports suggest that police suspect he may have been poisoned after threatening to expose a plan by Bo's wife Gu Kailai to move money abroad.
Speaking ahead of the meeting, a Downing Street spokeswoman said: "The Prime Minister will take the opportunity to raise the case of Neil Heywood, welcoming the launch of the Chinese investigation and emphasising that we are keen to address concerns about the suspicious circumstances of his tragic death. We want to see the conclusion of an investigation that observes due process."
Foreign Secretary William Hague said that Britain wants to see "the conclusion of a full investigation that observes due process, is free from political interference, exposes the truth behind this tragic case, and ensures that justice is done".
He told MPs that the Chinese investigation into Mr Heywood's death was launched after repeated requests from the UK.
In a written statement to the Commons, Mr Hague said Chinese officials initially informed the British consulate-general in Chongqing that Mr Heywood's death on November 15 last year was due to "over-consumption of alcohol". But he said the Foreign Office was made aware on January 18 of rumours within the British expatriate community calling into question the Chinese police findings.