US Defense Secretary Chuck Hagel will Tuesday urge China to pursue a more open dialogue about cyber-warfare and other sensitive issues to avert potential crises between the two powers, officials said.

Hagel was due to make the appeal in talks with his counterpart General Chang Wanquan in Beijing a day after Chinese officers allowed the Pentagon chief to tour the country's first aircraft carrier in Qingdao, a rare move by the usually secretive People's Liberation Army.

US officials said the visit to the carrier marked a promising step by the Chinese but the two sides remained deeply divided over regional territorial disputes, the threat posed by North Korea and cyber-spying, with each side trading accusations of digital espionage.

In a speech Tuesday at the PLA's National Defence University, Hagel planned to urge China to be more open about its cyber capabilities to defuse tensions and avoid an inadvertent conflict, a senior defence official said.

"We have tried to be as open and transparent on that as we can be. And we would like to see them be able to reciprocate," said the official, who spoke on condition of anonymity.

"We very recently shared with them some basic doctrine on cyberspace, on how we're approaching the challenges in cyberspace," the official told reporters travelling with Hagel.

But the Chinese so far had not "reciprocated", said the official, confirming a New York Times report.

- US invests in cyber warfare -

The United States is investing heavily in a new cyber warfare command and suspects PLA units are behind an increasing number of digital attacks on government and US corporate networks.

China, however, accuses the US of waging its own cyber offensive after revelations of far-reaching electronic espionage by the US National Security Agency, including media reports the spy service hacked into telecoms giant Huawei's network.

During his Asia tour, which included a visit to Tokyo, Hagel has stressed that as a "great power" China has to live up to its "responsibilities", suggesting Beijing should respect its smaller neighbours and adopt a more transparent approach in its relations with the US military.

Hagel "wants to have a frank discussion with Chinese leaders about those responsibilities", the defence official said.

Beijing and Tokyo are embroiled in a bitter row over disputed islands in the East China Sea controlled by Japan, with the tensions raising concerns about the possibility of a clash.

During his two-day visit to Tokyo -- with which Washington has a security alliance -- Hagel announced the deployment of two additional missile defence ships to Japan to counter the danger posed by North Korea, which recently test-fired medium range missiles.

Washington has pleaded with China to exert more pressure on its North Korean allies but has come away disappointed. Instead, the US has opted to bolster its military presence in the region and assist South Korea and Japan to thwart any potential missile attack from Pyongyang, officials said.

China showed off its sole aircraft carrier, the Liaoning, to Hagel on Monday, giving him a two-hour tour, including a briefing from the skipper and a walk on the flight deck.

"We didn't see every space aboard the ship but we felt this was an honest, genuine effort" to be more transparent, the official said.

The Chinese bought the Soviet-made warship from Ukraine and refitted it, putting the vessel into service in September 2012 in a milestone for the country's growing military might.