The US Secretary of Defense is adopting a less confrontational tone as he arrives in Beijing. It's Jim Mattis's first visit to China as Pentagon chief. Mattis says he is ready for a "conversation" with China and indicated he has an open mind. The discussions come after the US withdrew an invitation for China to participate in naval exercises in the Pacific, stepped up patrols in the South China Sea, and indicated it may start exercises with Taiwan. CGTN's Nathan King reports from Washington.

NATHAN KING WASHINGTON "Last month, the U.S. Defense Secretary criticized China's military behavior in the South China Sea, then shortly afterwards the U.S. flew B52 strategic bombers over contested waters, and stepped up so-called freedom of navigation operations. This followed disinviting China to the Rim of the Pacific exercises-the world's largest naval maneuvers. Chinese officials have warned that any stepped up engagement with Taiwan would be a, quote, red line. So, amid rising tensions, it's perhaps no surprise that James Mattis is talking softly while carrying a big stick."

JAMES MATTIS US SECRETARY OF DEFENSE "I'm going there (China) to get what I consider to be, straight from them, what they see for a strategic relationship. So, I want to go in right now without basically poisoning the well at this point, as if my mind's already made up. I'm going there to have a conversation."

NATHAN KING WASHINGTON "The visit also comes at a critical time for diplomacy over the Democratic People's Republic of Korea's nuclear and ballistic missile program. The Singapore summit was big on promises and short on details for denuclearization. Washington will need Beijing's help in the weeks and months to come. China has welcomed the decision to postpone joint U.S. military exercises with South Korea to give diplomacy a chance to work.

But away from the Korean peninsula, China will be looking for assurances that the U.S. is not taking sides in the South China Sea disputes and not violating Washington's longstanding 'one China policy' by increasing defensive ties with Taiwan. This will also be the first visit to Beijing by a U.S. secretary of defense since the U.S. officially labelled China an adversary, along with Russia. Mattis will visit allies South Korea and Japan before returning to Washington. Nathan King, CGTN, Washington."