* Risk aversion and repatriation flows boost yen
* Ratings agency comments weigh on sterling, euro
* China's commitment to buy Treasuries helps dollar (Adds details, updates prices)
By Vivianne Rodrigues and Nicholas Olivari
NEW YORK, March 9 (Reuters) - The yen gained broadly on Tuesday amid Japanese repatriation flows, while the euro declined on concerns that peripheral euro zone economies could face debt problems similar to those of Greece.
Appetite for risk had been boosted by Friday's stronger-than-expected U.S. employment report, pushing the yen down to two-week lows versus the euro and the dollar.
Comments from Fitch Ratings on Portugal's austerity measures on Tuesday, however, prompted a comeback for the yen and triggered further selling in the euro zone common currency.
The dollar was supported after China said it was committed to buying U.S. Treasuries. For details see [ID:nLDE6281JZ] and [ID:nBJC002514].
"The combination of today's risk-averse trading and repatriation of yen has been the key driver over the last 12 hours," said Camilla Sutton, currency strategist at Scotia Capital in Toronto.
Traders said Japanese exporters were in the market buying yen fairly actively, with further demand for the Japanese currency likely in the run-up to fiscal year-end on March 31.
"The feeling is that we are beginning to see fiscal year-end repatriation flows for Japan. The yen will remain in favor over the next few weeks as Japanese corporates bring money back home," said RBC currency strategist Adam Cole in London.
In late afternoon trading in New York, the dollar <JPY=> was trading down 0.4 percent at 89.93 yen.
The yen was up about 0.2 percent against the Canadian dollar <JPYCAD=R>, 0.9 percent against the Swiss franc <JPYCHF=R>, 0.6 percent against the euro <JPYEUR=R> and 0.9 percent against the pound <JPYGBP=R>.
Higher-yielding currencies such as the Australian dollar also fell against the Japanese currency. Aussie/yen <AUDJPY=R> slipped 0.2 percent.
Analysts at the Bank of Tokyo/Mitsubishi also noted that an incentive this year with Japanese corporations not having to pay the difference between local tax rates abroad and in Japan when funds are repatriated may play a greater role in bringing funds home in March. But the bank cautioned the impact of the incentive on the currency may be temporary.
Further yen gains could also be limited by speculation that the Bank of Japan may take additional steps to ease monetary policy. The BOJ is in the spotlight after the Nikkei newspaper reported on Friday that the central bank was examining easing again and may decide on such a move when it meets on March 16-17.
China, the world's biggest holder of foreign exchange reserves, renewed its commitment to the U.S. Treasury market on Tuesday but said it would be wary of substantially boosting its gold holdings.
"If China is not diversifying their reserves into gold, then there is no realistic alternative to absorb their demand outside of U.S. dollars," said Kathy Lien, director of research at GFT in New York.
The pound was under widespread pressure, dropping to a one-week low versus the dollar <GBP=> after ratings agency Fitch said Britain's sovereign credit profile had deteriorated.
Earlier, a Moody's Investors Service report saying Britain faces a difficult balancing act in deciding how and when to reduce support for the banking sector had also weighed on the pound. [ID:nLDE6271OB]
Against the dollar the pound was down around 0.5 percent at $1.4990.
The euro was down around 0.3 percent against the dollar <EUR=> at $1.3595, continuing to struggle in the face of debt concerns in euro zone countries such as Greece and Portugal.
Fitch Ratings said on Tuesday it still has a negative outlook on Portugal's AA ratings and was studying details of the country's new austerity measures announced Monday.
"Even though Fitch also stated that the contagion risk to Portugal and Spain from Greece is not great, there are sufficient worries in the market concerning EMU to keep the euro 'on the back foot'," said FOREX.com analysts in a note.
Greek Finance Minister George Papaconstantinou said on Tuesday in Washington his country was taking necessary steps to get its budget under control but said the issue was also a European one. [ID:nWEN1451]
Greece has been a drag on the euro in 2010, which has lost 5 percent against the dollar so far this year and 8.1 percent against the yen. (Additional reporting by Neal Armstrong in London; Editing by James Dalgleish)