Updates as at 0627 GMT

By Rishav Chatterjee

Feb 3 (Reuters) - Emerging Asian currencies and shares tumbled on Monday after U.S. President Donald Trump slapped tariffs on imports from the country's three biggest trade partners, stoking fears of a trade war and its impact on export-focused economies in the region.

Markets were downbeat in Asia, with stocks reliant on exports getting hit the most, ranging from Japanese automakers to chipmakers in Taiwan, South Korea, to Chinese e-commerce firms.

As Trump had promised last month, the United States hit Canada and Mexico with duties of 25% and China with a 10% levy, with retaliatory moves immediately promised by Canada and Mexico, the top two U.S. trading partners. China said it would challenge Trump's levies at the World Trade Organization.

The reality of a trade war sent the Mexican peso MXN= to its lowest in nearly three years, the Canadian dollar CAD=D3 to a 22-year low and offshore yuan CNH=D3 to a record low.

All currencies in Asia slumped, with the Thai baht THB=TH and Indonesian rupiah IDR= among the top losers.

"In the weeks ahead, tariffs are likely to represent an overhang on markets and contribute to volatility, at least until investors gain greater clarity on the path and destination of U.S. trade policy," UBS analysts said.

Markets in Taipei .TWII fell 3.5% while Seoul .KS11 was 2.5% lower, weighed down by exporters.

Chip exporters Samsung Electronics 005930.KS and Taiwan Semiconductor Manufacturing Co (TSMC) 2330.TW plunged 2.7% and 5.7%, respectively. TSMC was seen playing catch-up with the global sell-off in artificial intelligence-related stocks last week when Taiwan was closed for the Lunar New Year.

Bangkok stocks .SETI traded around an over-five-year low.

Shares in Jakarta .JKSE lost 2.2% in its weakest trading session in six months. Heavyweight coal miner Adaro Andalan AADI.JK and Adaro Minerals ADMR.JK fell 4.5% and 8% each, dragging the local benchmark.

Indonesia, Southeast Asia's largest economy, reported annual inflation below the central bank's target range, a sign that a surprise policy easing last month boosted spending and bolstered the case for another rate cut.

The rupiah was trading 0.9% lower against the greenback.

The Indian rupee INR=IN further weakened to a fresh low, as investors bet on rate cuts by the local central bank.

The Philippine peso PHP= and the Malaysian ringgit MYR= dropped 0.4% and 0.8%, respectively.

HIGHLIGHTS:

** Indonesia's inflation in Jan at 0.76% y/y

** Thai central bank says economy slowed in December

(Reporting by Rishav Chatterjee in Bengaluru; Editing by Christopher Cushing)

((Rishav.Chatterjee@thomsonreuters.com;))