HONG KONG, March 26 (Reuters) - UBS plans to tap growth in Asia and increase assets sourced from clients in the region to 20% in five-six years, Chief Executive Sergio Ermotti said on Tuesday.

This would be up from around 15% of its $5.2 trillion assets the Swiss banking giant currently manages globally, according to Ermotti who spoke at the Milken Institute Global Investors' Symposium held in Hong Kong. (Reporting by Kane Wu and Julie Zhu; Writing by Selena Li; Editing by Muralikumar Anantharaman)