Greece's liquidity problems are "insignificant", the country's finance minister said on German television on Sunday, pledging that the Greek government would take all steps necessary to repay its debts.

"We want a successful Europe, a successful currency union," Yanis Varoufakis told a panel discussion on German broadcaster ARD, describing liquidity problems as "insignificant" and "small" when answering a question about repayment of debt.

"Our intention is to do everything necessary to pay back every single euro," he said, suggesting, however, that a restructuring of debt would be the "best way of helping Greece to do so".

Varoufakis refused to be drawn on the question of World War Two reparations to Greece from Germany. Leftist Prime Minister Alexis Tsipras has accused Berlin of using legal tricks to avoid paying compensation for the Nazi occupation.

"It's not about money," Varoufakis said in the moderated discussion. "It's a moral question. I would be happy if it was off the table."

Tsipras has tried to reassure euro zone partners that Greece will stick to an extended bailout agreement with its international creditors, as relations between Greece and euro zonepaymaster Germany have grown increasingly strained.

Greece has submitted a formal protest to the German Foreign Ministry, accusing Finance Minister Wolfgang Schaeuble of having insulted his Greek counterpart, Varoufakis, further eroding the relationship.