The euro fell against both the dollar and yen on Tuesday on renewed worries about Greek debt while world shares were flat with Europe higher.

Jitters about Greece returned to the market after a newspaper report said it was seeking $5 billion to $10 billion from U.S. investors to help cover its May borrowing requirement. ]

The process of seeking the funding looks likely to be akin to an emerging market, including a roadshow.

Greece was also reported separately to be seeking to amend the deal struck late last month with European Union partners to provide an emergency safety net.

One result was a sell-off in the euro, which was down half a percent against the dollar at $1.3417 and around 1 percent against the yen at 125.94 yen.

There's speculation that the financial situation in Greece will become increasingly difficult, said Lutz Karpowitz, currency strategist at Commerzbank in Frankfurt. Negative news about Greece will continue to pressure the euro.

Euro zone government debt also fell. The June Bund future was down 64 ticks on the day at 122.80.

The interest rate-sensitive two-year Schatz yield was up 5.5 basis points at 1.03 percent. The 10-year Bund yield was up eight basis points at 3.163 percent.

Five-year Greek credit default swaps -- the cost of insuring Greek debt -- rose to 354 basis points from 347 basis post on Friday, the last day they were priced.

Euro zone bonds were also catching up from the long Easter weekend, which saw some positive U.S. economic data, including on jobs.

EUROPE STOCKS RISE

Word stocks as measured by MSCI <.MIWD00000PUS> were flat to higher, with European stocks holding up the benchmark.

European shares hit a new 18-month high, tracking gains in the United States, where sentiment was boosted by a stronger labor market.

The FTSEurofirst 300 <.FTEU3> index of top European shares was up half a percent after rising 1.4 percent in the previous session to its highest close since September 2008.

The European benchmark is up more than 70 percent from its low of March 9, 2009.

Earlier, Japan's Nikkei average fell 0.5 percent, but only after successive days of 18-month highs.

(Additional reporting by Naomi Tajitsu and George Matlock, editing by Mike Peacock)

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