(Fixes typographical error in third paragraph)
* Q4 GDP grows annualised +1.0 pct vs f'cast +1.1 pct
* Private consumption 0.0 pct qtr/qtr vs flat f'cast
* Capex +0.9 pct qtr/qtr, matching f'cast
* External demand spurs growth, domestic demand flat
By Tetsushi Kajimoto and Stanley White
TOKYO, Feb 13 (Reuters) - Japan's economy grew for a fourth straight quarter in the final three months of last year as a weaker yen supported exports, but tepid private consumption and the risks of rising U.S. protectionism cast doubts over a sustainable recovery.
Data on Monday showed the world's third-largest economy grew an annualised 1.0 percent in October-December, roughly in line with the 1.1 percent increase markets had expected, following a revised 1.4 percent expansion in July-September.
Japan's export-driven growth over the quarter has helped fill the economic shortfall left by anaemic domestic demand, but accompanying this tailwind are concerns Japan's persistent trade surplus with the U.S may make it a target of U.S. President Donald Trump's criticism.
During a weekend meeting with Prime Minister Shinzo Abe, Trump held off from his previous rhetoric against Japan for using its monetary stimulus to weaken the yen and gain an unfair trade advantage. But analysts doubt a honeymoon would last long.
Economy Minister Nobuteru Ishihara said Japan remained in a moderate recovery trend and expected the positive momentum to be maintained, but he sounded a cautious note on the outlook.
"Attention should be paid to uncertainty over global economy and fluctuations in financial markets," he told reporters after the GDP data release.
Analysts were equally cautious about the outlook even as a weak yen has provided exports a lift.
"The fact that the economy grew a fourth straight quarter on the back of exports should be considered a passing mark for policymakers," said Hidenobu Tokuda, senior economist at Mizuho Research Institute.
"Still, the corporate sector strength has not spread to households who are facing higher costs of living and future uncertainty. The key is how price-adjusted real wages grow to support private consumption from now on."
The preliminary reading for fourth-quarter gross domestic product (GDP) figure translated into 0.2 percent growth on a quarter-on-quarter basis, versus a 0.3 percent gain expected by analysts.
External demand - or exports minus imports - contributed 0.2 percentage point to GDP, with exports rising 2.6 percent, the fastest growth in two years, on shipments of cars to China and the United States, and those of electronics parts to Asia.