(Reuters) - Allianz chief economic adviser Mohamed El Erian told CNBC television on Tuesday that he sees the potential for a Greece debt "accident" at about 55 percent and rising, as the chances of a default continue to grow. El Erian told the business news channel that based on recent discussions with people in Europe, there is more confidence that any contagion arising from a default would be limited, and there is even talk the euro zone would be better off if Greece left the European Union. Greece is set to default on a 1.6 billion euro (1.16 billion pound) debt repayment to the International Monetary Fund on June 30, possibly driving it to leave the euro zone unless it receives fresh funds.