* Spreadbetters see stronger opening for European bourses
* Debt deal a relief but Greece not seen out of woods yet
* Oil gives up gains made on cautious optimism over Greek deal
* German Ifo survey, Yellen testimony in focus
By Hideyuki Sano and Lisa Twaronite
TOKYO, Feb 23 (Reuters) - Asian shares were flat on Monday as many countries in the region returned from Lunar New Year holidays, with sentiment supported by relief that Greece reached a deal to avert an immediate fiscal crisis.
Euro zone ministers late on Friday agreed to extend Greece's financial rescue package by four months, a shorter extension that the six months the country had sought. Relief over the last-minute deal boosted Wall Street shares to record highs, and was likely to jump-start European markets.
Spreadbetters saw Britain's FTSE 100 and Germany's DAX opening about 0.5 percent higher, and France's CAC 40 up 0.8 percent. The Greek stock market will be closed on Monday for a public holiday.
"Friday's agreement between Greece and the EU left both sides claiming victory, as well as pushing stock markets in the U.S. to record highs, and looks set to see European markets open higher this morning with the FTSE100 potentially opening at a record high," Michael Hewson, chief strategist at CMC Markets in London, said in a note to clients.
But Asian markets as a whole saw little follow-up buying after the U.S. gains. MSCI's broadest index of Asia-Pacific shares outside Japan was virtually flat from its Friday close, after earlier drifting lower.
U.S. stock futures were also nearly flat in Asian trading, but Japan's Nikkei took a cue from Wall Street's Greek-relief rally to rise 0.7 percent and notch another 15-year high.
"The debt deal is giving comfort to the market," said Masashi Oda, chief investment officer at Sumitomo Mitsui Trust Bank, adding that investors' risk appetite for Japanese shares is mainly due to their attractive valuations.
Activity in Asia is expected to pick up this week as many market players return from Lunar New Year holidays, with mainland Chinese markets set to remain closed until Wednesday.
Oil prices wobbled, as cautious optimism about the Greek debt deal struggled to offset supply concerns. Brent pared gains and was slightly higher at $60.24 a barrel, while U.S. WTI crude erased its earlier rise and dropped about 0.3 percent to $50.66.
Greece has to provide a list of reform measures to euro zone by Monday to secure financing, but domestically it came under attack for selling "illusions" to voters after failing to keep a promise to extract the country from its international bailout.