Timeline: The obstacle course for China-U.S. ties in 2010

BEIJING (Reuters) - Two senior White House advisers, National Economic Council Director Larry Summers and Deputy National Security Adviser Thomas Donilon, are holding talks in China covering the two powers' broad ties.

Beijing and Washington have gone through bouts of tension in 2010 but will try to steady relations ahead of a G20 summit and planned visit to Washington by Chinese President Hu Jintao. Here is a timeline of relations this year:

January 12 - Google threatens to pull out of China over censorship and hacking attacks from within the country.

January 29 - Obama administration tells U.S. Congress of proposed arms sales to Taiwan worth $6.4 billion. China condemns the sales and threatens sanctions on companies involved.

February 18 - Obama meets the Dalai Lama, the exiled Tibetan leader, at the White House. China reviles the Dalai Lama as a separatist for advocating self-rule for Tibet and condemns the meeting.

March 15 - Members of U.S. Congress issue letter demanding more pressure on China to let its currency appreciate. The next day, a bipartisan bill on the issue goes before the Senate.

March 22 - Google shuts its China-based search service Google.cn and begins redirecting mainland Web searchers to a portal in Hong Kong.

April 3 - U.S. Treasury Secretary Timothy Geithner says he is delaying an April 15 report on whether China manipulates its currency but vows to press for a more flexible Chinese yuan.

April 12-13 - Obama hosts a multi-nation nuclear security summit in Washington attended by Chinese President Hu.

May 13-14 - The United States and China resume a formal bilateral dialogue on human rights after a two-year hiatus.

May 18 - China joins the four other permanent members of the United Nations Security Council, including the U.S., in backing a Security Council resolution authorizing expanded sanctions against Iran over its disputed nuclear activities.

June 19 - China's central bank says it will gradually make its yuan exchange rate more flexible, softening a 23-month-old dollar peg under intense fire from Washington.

June 28 - Obama administration declines to label China a currency manipulator in a report delayed from April.

July 9 - China joins U.S. and other permanent members of U.N. Security Council in issuing a statement condemning an attack that sank the South Korean naval ship, the Cheonan, but statement stops short of directly blaming North Korea.

July 23 - China angered after the United States takes up the issue of disputes in the South China Sea at a regional forum.

July 17 - China holds first of several military drills in the Yellow Sea, after objecting to U.S.-South Korean plans for joint drills elsewhere in the sea.

August 30 - North Korean leader Kim Jong-il finishes a five-day visit to neighbor China. Washington announces new bilateral sanctions against the North.

October 15 - Next semi-annual U.S. Treasury report on foreign exchange rate policies due. Obama administration will again have to decide whether to label China a currency manipulator.

November 11-12 - South Korea to host second summit for the year of the G20 group of major rich and developing economies, where Hu and Obama will have a chance to meet.

November 13-14 - Asia-Pacific Economic Cooperation summit in Yokohama, Japan, another opportunity for the two leaders to meet.

(Reporting by Chris Buckley in Beijing; Jim Wolf, Doug Palmer and Paul Eckert in Washington; Ralph Jennings in Taipei; Editing by Ken Wills)