The Chinese government has threatened to halt judicial co-operation with the US if a federal prosecutor does not agree to return one of Beijing’s most wanted men, according to Chinese and US officials familiar with the extradition negotiations.

China’s public security ministry began pushing last year for the return of Ling Wancheng, a businessman now residing in the US. Mr Ling’s brother, Jihua, was chief of staff for former Chinese president Hu Jintao and is one of the highest-ranking officials caught up in the ruling Communist party’s anti-corruption campaign.

Over recent months, Chinese police have informed their US counterparts that they would withhold future co-operation if Washington did not agree in principle to Mr Ling’s return this month, according to officials familiar with the extradition negotiations.