Jia Yueting, CEO of Leshi Information Technology Co (Letv), was forced by overwork to cancel his participation in a business delegation accompanying Chinese President Xi Jinping's UK state visit, a company source said.

Four days before the trip, Jia was "fully engaged" in planning an important press conference for October 27, a source close to Letv who declined to be identified, said Wednesday. Jia became ill from overwork and has been in the hospital since then, according to the source. 

In addition, Jia has not fully recovered from previous thyroid surgery, which forced him to cancel the UK trip, the source noted.

The company regrets that Jia could not make the trip, according to the source.

Jia is now receiving a three-week course of treatment, according to media reports.

Still, the source noted that cooperation with UK-based vehicle producer Aston Martin is going smoothly, and Letv is also actively pursuing its strategy in the car industry. For example, the company announced an investment in Chinese car-hailing services provider Yidao Yongche on Tuesday, aiming to move into the fast-growing ride-sharing industry.

Organized by the China Council for the Promotion of International Trade, the delegation includes leaders in finance, infrastructure, energy and investment. That's a contrast to the delegation that accompanied Xi during his visit to the US, which featured Internet companies, news portal yicai.com reported, citing London-based anonymous sources.

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