1. Most Asian losses came ahead of a key meeting of leaders from the Group of 20 major economies, where the European crisis was expected to feature high on the agenda.

2. On Wednesday in an emergency meeting prior to the G-20 summit, France and Germany warned Greece to accept the latest package of measures or lose its aid after Greece called a referendum.

3. EU leaders are now seriously beginning to consider the prospects of a Greek exit from the euro zone while taking a tougher stance on Greek highlights how important the Dec. 4 referendum will be.

As such stock markets are set to remain highly nervous before the vote, with risk aversion set to remain elevated.