* Nikkei posts a 2.2 pct weekly drop
* Nikon tumbles 12 pct on cut in imaging business forecast
* Sony soars after announcing share buyback
By Ayai Tomisawa
TOKYO, Feb 8 (Reuters) - Japan's Nikkei closed at a one-month low on Friday, as renewed worries about the United States-China trade dispute plus dismal earnings from Japan Inc hurt risk appetites.
The Nikkei share average sank 2 percent, its biggest one-day loss since early January, to 20,333.17, its lowest closing level since Jan. 10. For the week, the Nikkei shed 2.2 percent.
U.S. President Donald Trump said he did not plan to meet Chinese President Xi Jinping before the March 1 deadline set by the two countries for reaching an agreement.
"Investors are getting nervous since the market had been optimistic about a resolution of the trade dispute since the beginning of the year," said Shusuke Yamada, chief Japan FX strategist at Bank Of America Merrill Lynch.
The Japanese market was already under pressure with some blue-chip companies cutting profit forecasts.
According to Daiwa Securities, out of 200 major companies it covers, 117 reported their third-quarter results as of Feb. 6 - and 31 of those cut their annual forecasts on a pretax profit basis.
On Friday, Nikon Corp dived 12 percent after it reduced the annual operating profit forecast for its imaging business on struggling camera and chip equipment operations, hit by falling demand in China.
Risk aversion among investors dragged down cyclical stocks such as machinery firms that have large exposure to China. Fanuc Corp tumbled 4 percent, Komatsu Ltd 3 percent and Hitachi Construction Machinery 4.4 percent.
Bucking Friday's weakness, Sony Corp surged 4.1 percent after it announced a share buyback of 100 billion yen ($910 million) - its first aimed at boosting shareholder returns.
The broader Topix declined 1.9 percent to 1,539.40, with one but all of its 33 subsectors in negative territory.
Declining issues outnumbered advancing ones 1,801 to 288. (Editing by Richard Borsuk)