* Greenback hits 10-month high vs euro, others
* Greece in focus as EU leaders meet
* World stock flat, weakened by emerging markets
By Jeremy Gaunt, European Investment Correspondent
LONDON, March 25 (Reuters) - The dollar rose to a 10-month high against the euro and a basket of other major currencies on Thursday before slipping back slightly, as jitters over euro zone debt combined with a general flow towards relative safety.
World stocks as measured by MSCI <.MIWD00000PUS> were flat, with gains in Europe offset by weak emerging markets.
Investors continued to show concern about stability in the euro zone on the back of ongoing Greek troubles and Wednesday's downgrade of Portuguese debt.
Diplomatic efforts continued ahead of a European Union summit to start on Thursday after they failed on Wednesday failed to bridge differences over whether to offer a safety net to Greece. [
]The euro has been punished by uncertainty engendered by what comes down to a fight about whether one euro zone country should bail out another.
The single currency recovered slightly to $1.3330 <EUR=> after hitting a low of $1.3285 in Asian trading.
"Short-term speculators are probably all short on the euro, but there are long-term investors who are patiently holding back," said Kazuyuki Takami, senior manager of foreign exchange trading at the Bank of Tokyo-Mitsubishi UFJ.
"But depending on the developments, those long-term investors could also start dumping the currency, taking it further and further down," he said.
Dubai's debt issues were also in focus again after the emirate's government said it would support the restructuring of debt-laden state-owned firm Dubai World and its Nakheel subsidiary by providing $9.5 billion in new funding.
Euro zone government bond prices were slightly lower, catching up with moves in the U.S. Treasury market which sold off late the previous session after poor demand in a five-year note auction.
EMERGING UNDERPERFORMANCE
European shares edged up, helped by oil majors gaining as commodity prices eased off lows.
The pan-European FTSEurofirst 300 <
> index of top shares was up 0.1 percent at 1,076.38 points.But emerging market shares <.MSCIEF> were down nearly a quarter of a percent.
Despite continually being cited as a favourite by institutional investors, emerging market shares have underperformed this year and the MSCI benchmark is barely in positive territory.
Some investors may be pulling back because of concerns that too much money is chasing too few assets could create a short-term bubble. [
]Earlier, Japan's Nikkei closed up 0.02 percent <
>.(To read Reuters Global Investing Blog click on http://blogs.reuters.com/globalinvesting; for the MacroScope Blog click on http://blogs.reuters.com/macroscope)
(editing by John Stonestreet)