Europe's economics commissioner, Pierre Moscovici, said today he was confident Greece was "turning a page" from economic crisis and would successfully conclude a bailout programme which expires in August 2018.

But Moscovici, who was visiting Athens, said the crisis-hit country was at a crucial juncture and urged Greece to keep up economic reforms.

He also said he was confident Greece could return to bond markets at "logical yields".

"Returning to the markets is an important first step," Moscovici told reporters.

Greece concluded a bailout review last month, paving the way for the disbursement of further funds after more reforms to its pension and tax systems.

On Tuesday, after a three-year hiatus, it launched a return to bond markets, widely seen as a test run for authorities before its third financial bailout from international lenders expires next year.

"It is also a signal to markets that Greece is showing results as far as its commitments are concerned and the reforms which have been decided and is back onto a path of sustainability," Moscovici said, speaking through an interpreter.

Greece has invited holders of its 4.75 per cent outstanding bonds maturing in 2019 to tender them for cash, along with a plan to offer new five-year paper.

The country last ventured onto bond markets with two issues in 2014, a year before it lurched into crisis in a standoff with lenders which culminated in a third financial bailout in mid 2015.

Greek PM Tsipras and EU commissioner Moscovici sat down for talks in Athens. Photo: Reuters

Moscovici said it was crucial for Greece to keep up reform momentum, comparing it to riding a bicycle.

"Confidence in Greece is really coming back, but we need to continue the good work. We need to be on the bicycle, and to keep on pedalling."

"That's the case for Europe, as a whole. If you don't go that way, that bicycle falls."

He also said that Greece's official creditors must keep up promises on debt relief that were agreed in a Eurogroup meeting of eurozone finance ministers in June.

"The (debt relief) measures must be implemented at the end of the bailout programme, but the decisions can be taken before that," Moscovici said. "We must continue to work hard towards completing the programme."