The U.S. 10-year Treasury could very well fall below 1 percent, Mohamed El-Erian, Allianz's chief economic adviser, said Wednesday.

El-Erian spoke after the benchmark bond yield closed Tuesday at new low of 1.375 percent as investors flocked to safe haven assets after Britain's vote to leave the European Union. The 10-year was up slightly at 1.381 percent midmorning Wednesday.