That was a marked difference with the tone of statements made last summer, when some Merkel allies were openly dismissive of the Greeks for alleged economic mismanagement. Some politicians even suggested that Greece's departure from the common currency would not produce the economic shock that many fear.
The visit was also likely aimed at preventing the opposition Social Democrats from criticizing her for allegedly failing to display strong personal leadership in the euro crisis in the run-up to national elections expected in about a year.
Merkel told reporters in Athens that the troika report was "taking longer than was originally thought."
"But it's better to deal with problems in detail that to try and address them quickly," she said.
A senior Greek government official said rescue creditors had given the country a list of around 90 structural reforms to be approved immediately so that the vital next loan installment could be paid sometime next month.
The official asked not to be named, since talks between Merkel and Samaras were ongoing.
AP writers in Berlin and AP television and photography staff and in Athens contributed.
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