German lawmakers have approved a bill to increase the size of a bailout fund for struggling eurozone countries.

The lower house of parliament voted to expand the fund to $593 billion dollars on Thursday. The vote was seen as a key test of German Chancellor Angela Merkel’s center-right coalition.

The $593 billion figure was agreed to by European leaders more than two months ago. Finland approved the increase on Wednesday. Six other countries have yet to ratify it.

Thursday’s vote came as auditors from the International Monetary Fund, European Central Bank and European Union resumed talks with Greece on its debt crisis. They are in Athens looking at Greek efforts to slash its huge debt. The inspectors will recommend whether Greece is to get another installment of last year’s $159-billion bailout.

The Greek Parliament approved a controversial new property tax Tuesday, trying to show its lenders that Greece is committed to economic reform. But Deputy Prime Minister Theodoros Pangalos said on Greek television Wednesday that Greeks are exhausted by taxes.

Meantime, some financial experts say $593 billion is not enough and that several trillion dollars are needed to deal with Greece’s debt woes, bailouts for Ireland and Portugal, and possible aid for Italy and Spain.