Mohamed El-Erian: Fed to begin raising rates in September, "the loosest tightening" ever

Allianz chief economic advisor Mohamed El-Erian speaking a little earlier on CNBC:

• Believes the Federal Reserve will begin raising rates in September
• Says it will be "the loosest tightening" the Fed has ever done
• "We're going to end way below historical levels. The Fed is going to work very hard to get us off the obsession of the date and focus more on what is going to be a very, very gradual journey."

On Europe:

• The ECB will do what it can to help Greece
• It doesn't want to cause the first exit from the euro zone
• But El Erian is worries there will be an "accident," like capital controls or small defaults, that will ultimately push Greece out of the euro zone
• In the short term, a Greek exit will shock the market, but long term it won't make a huge difference