Germany's economy minister on Monday warned against euphoria in the wake of Greece's approval of key austerity measures, and defended the pressure that both Berlin and Brussels have exerted on Athens.

Speaking on ARD public television, Philipp Roesler said that the approval late on Sunday in the Greek parliament of a raft of unpopular savings was "basically a must" but still "a step in the right direction."

Nevertheless, he insisted that a report drawn up by Greece's main creditors -- known as the "troika" -- would be the decisive factor in whether Athens received more cash to stave off bankruptcy.

"It is good that the laws were passed and with a large majority but what counts now is the implementation of structural reforms," added Roesler.

"We have gone a step in the right direction, but we are still a long way from the goal," he said.

He recalled that certain laws on tax reform had previously been passed in the Greek parliament but were not sufficiently implemented, which he said was "part of the problem" that Athens now faces.

"We have to see the troika report. They will assess whether the measures are sufficient to assure Greece's debt sustainability.

"We want to see what comes after the legislative process because the legislative process is one thing, implementation is another."

He stressed that the pressure that Germany and the EU had applied on Greece to push through unpopular and harsh austerity measures "had been the right thing to do to push Greece forward."

The parliamentary vote was accompanied by a protest of 100,000 people which turned violent, with diehards brandishing homemade flame throwers, in addition to the usual petrol bombs.