German Finance Minister Wolfgang Schaeuble kept up the pressure on Greece’s radical leftist government on Wednesday, underlined that before any further financial aid can be disbursed Athens must prove it has fulfilled conditions of its bailout program.

His statements were carried in a German newspaper.

“Athens has to prove that it has fulfilled the agreed conditions, before any further finds can be disbursed” Schaeuble said, adding that “how long Greece needs to fulfill the terms” is up to the Greek government.

He also warned the Greek Finance Minister against trying to change the terms of the current agreement, stating that if Yanis Varoufakis “declares that the Eurogroup’s agreement with Greece is unclear, he will do so against his better judgment.”