TOKYO, JAPAN - Toyota Motor Corp said on Tuesday it will cut management bonuses by 10% as the global economic slowdown bites hard and prompts it to reduce production further in Japan.

The world's largest automaker is cutting bonuses for roughly 5,000 managers as the downturn keeps customers away from showrooms worldwide, a company spokesman said.

Automakers are reeling from the worst downturn in decades as sales slump in the United States and Europe and even in developing markets such as China, which carmakers had hoped would fuel near-term growth.

With inventory building everywhere, carmakers are cutting back production, extending temporary plant closures and seeking help from governments to ride out savage cutbacks in consumer spending.

Toyota will halt production at one of three assembly lines at its Tahara factory in central Japan for two days at the end of this month, resulting in a loss of less than 5,000 cars, another spokesman said. The line produces the LS, GS and IS models for the premium Lexus marque.

Car sales in Japan, excluding 660cc minivehicles, fell 27% in November, industry data showed on Monday, with sales tumbling at Toyota and its rivals Nissan Motor Co and Honda Motor Co.

Lexus sales in Japan are down 24% in the year to date and are falling hard also in the United States, the brand's main market.

Another factory in southern Japan operated by a subsidiary and which builds Lexus models is also set to halt production for two days, local media said.

Confidence among Japanese manufacturers fell at its sharpest pace on record in November, the Reuters Tankan showed on Tuesday, with the automotive sector reporting one of the weakest readings. The Reuters Tankan is a monthly poll of big Japanese firms that tracks the Bank of Japan's closely watched quarterly tankan, next due on Dec. 15.

Toyota is set to disclose far weaker sales and production estimates for 2008 and 2009 at a year-end news conference later this month after lowering the projections once this summer.

Toyota slashed 1 trillion yen ($10.7 billion) from its annual operating profit forecast last month and has set up an emergency committee aimed at improving short-term profitability in the face of growing headwinds.

Shares at Toyota fell 3.6% to 2,840 yen in morning trade, outperforming a 4.6% slide in the Nikkei. (Reporting by Mayumi Negishi and Chang-Ran Kim; Editing by Edwina Gibbs)