The latest US suspicion of Chinese hacking of government computers has further shadowed the annual meetings between top officials of the two countries.The accusation, one of the many hacking charges the US has pinned on China despite its own massive surveillance on world leaders, research institutes and private phone calls, highlights the growing strategic importance of cyber space and deepened mistrust between the two countries.

CNN reported Tuesday that the personal data of an estimated 18 million federal workers was affected by a cyber-breach at the Office of Personnel Management (OPM), more than four times the 4.2 million the agency has publicly acknowledged. It said that the investigators believe the Chinese government is behind the cyber attack.

Chinese foreign ministry spokesperson Lu Kang said on Tuesday that cyber security is a challenge faced by the entire international community and solving the problem requires effective cooperation based on mutual respect.

"China and the US had previously always had a good dialogue mechanism on issues of Internet security. Because of reasons that everyone knows about, and not because of China, this dialogue has stopped," Lu said.

China withdrew from a bilateral working group on cyber security last year after the US charged five Chinese military officers of hacking American firms.

"The US has to properly handle relevant issues in order to create conditions for the resumption of the dialogue," Lu said.

The US government has not formally accused China of hacking OPM computers.

An expert who requested anonymity said that computer hacking has been a "common" charge brought by the US against China and "it's unlikely that this issue would dominate the talks."

Zhang Jiadong, a Fudan University professor, said that it could be because the lack of sound evidence that the White House is hesitant to pin the incident on Beijing. "It's funny because the US has absolute advantage in cyberspace in terms of technology and China is known to be no match," Zhang told the Global Times.

Nine out of 13 root name servers are located in the US, two in Europe and one in Japan.

The US government has hacked into the cellphones of world leaders including German Chancellor Angela Merkel. The National Security Agency (NSA) also broke into Chinese mobile phone companies to collect text messages and spied on Tsinghua University, home to one of China's six major backbone networks, according to former NSA contractor Edward Snowden.

"I believe the US is using the accusation to gain a strategic and psychological advantage in the high-level talks," Zhang said.

Analysts also see the accusations as indicative of the growing strategic importance of cyberspace. "The US looks at cyber warfare as if it were a real war and it is possible that someday it could guide the real world," the expert said.

On Monday, US Deputy Secretary of State Antony Blinken and China's Executive Vice-Foreign Minister Zhang Yesui held talks between civilian and military officials to discuss security issues.

Later that day, US Secretary of State John Kerry and Treasury Secretary Jacob Lew also hosted China's Vice-Premier Wang Yang and State Councilor Yang Jiechi for a private dinner before the seventh US-China Strategic and Economic Dialogue (S&ED) kicks off on Tuesday.

Chinese Vice Premier Wang Yang said China and the US should not follow the old path of the confrontation of two powers. "We may not get a win-win situation on all things through dialogue, but we'll definitely see a lose-lose situation through confrontation," he said at the opening ceremony on Tuesday in Washington, according to Chinese news portal ifeng.com.

US Vice President Joe Biden said China and the US might not resolve all of their differences during the meetings, but should commit to working on them. He also said the US welcomes "healthy and fair competition" from China.

Without mentioning China by name, US Treasury Secretary Jack Lew said Washington remained "deeply concerned about government-sponsored cyber theft from companies and commercial sectors," according to Reuters.

Reuters contributed to this story