UPDATE 1-France's Sarkozy says euro is too strong

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LONDON, March 27 (Reuters) - French President Nicolas Sarkozy said on Thursday that the euro was too strong and questioned whether current monetary imbalances were sustainable.

"When I was a student, I was taught that a strong economy has a strong currency," Sarkozy said in a speech at a dinner in London's financial district that ended his two-day state visit to Britain.

"What do I see today? The opposite. The dollar has never been so weak, the yuan is as weak as ever, the yen is the same. And the euro, which has too weak growth, is at too high a level."

"Who can believe that the monetary imbalances which led to today's situation can persist?" he asked.

Sarkozy, for part of last year, was an isolated but vociferous critic of the euro's rise on the foreign exchanges.

However, more and more European countries have expressed similar concerns about the damage the strong euro risks inflicting on exports as the single currency has risen further and further, hitting a record high above $1.59 last week.

The euro accumulated gains of more than 12 percent against the dollar in 2007 and another 8 percent so far this year.

Sarkozy, who departed from his prepared text, also took aim at credit rating agencies, which have been criticized by many investors for failing to act earlier to lower some ratings.