Germany's Finance Minister Wolfgang Sch?uble has made clear he considers a Greek exit from the Eurozone (a so-called Grexit) possible, amid a harsh verbal clash with Greek politicians.

"As the responsibility, the possibility to decide what happens, lies only in [the hands of] Greece, and as we do not know what those responsible in Greece are doing, we cannot rule it out," Sch?uble said on Thursday evening, while on a visit to Austria to meet counterpart Hans J?rg.

Athens is currently in talks on receiving additional assistance from the European Central Bank in return for more reforms.

Sch?uble reiterated the country could count on new strings of cash only if it sticks to its commitments to international creditors.

"Europe stands ready to help Greece, but Greece must also allow help. The problem cannot be solved by making others scapegoats," German daily Frankfurter Allegemeine Zeitung quoted him as saying.

Sch?uble's comments follow renewal of tensions between him and his Greek counterpart Yanis Varoufakis.

Amid days of technical talks held among Eurozone finance ministers on the extension of Greece's bailout program, the German politician reportedly called Varoufakis "foolishly na?ve," and Athens lodged a complaint. However, German media outlets suggest the scandal might be a result of bad translation.

Earlier this week, Greek PM Alexis Tsipras also declared his country would seek again German reparations for World War Two, a demand which added to tensions.