Following President Xi's arrival in London, US security firm CrowdStrike Inc claimed that hackers associated with the Chinese government had tried to penetrate at least seven US companies, despite Washington and Beijing agreeing not to spy on each other for commercial reasons.
CrowdStrike Inc said it detected and rebuffed the attacks on five technology and two pharmaceutical companies, stating that it believed the hackers were affiliated with the Chinese government due to the types of servers and software used.
The claims comes after US and Chinese officials agreed on September 25 that neither government would knowingly support cyber hacking of corporate bodies in order to assist local businesses.
Following the claims, Chinese Foreign Ministry spokeswoman Hua Chunying said the government doesn't support hacking for the purpose of stealing commercial secrets.
"Internet hacking attacks are marked by their secretive, cross border nature."
US officials have not commented on the CrowdStrike Inc report, however the release of such claims comes at an increasingly tense time in American-Chinese relations.
President Xi's visit to the UK is expected to anger officials in Washington, who have been at loggerheads with Beijing over a number of contentious issues in Asia.
The US has accused China of acting aggressively over a number of contested islands in the South China Sea and recently completed negotiations for the Trans-Pacific Partnership (TPP), seen as a political move to isolate China and counter its growing economic power in the region.
UK Prime Minister David Cameron has rejected calls that Britain's wooing of China may affect its 'special relationship' with the US.
"We see no conflict with having that very special relationship, with wanting to be a strong partner for China as the Chinese economy continues to grow and China emerges as an enormous world power."
However, others have suggested Xi's trip to London, UK Chancellor George Osborne's September visit to China and Britain's membership in China's new Asia Infrastructure Investment Bank (AIIB), will damage the US-UK alliance.