BANGKOK, July 29 (Reuters) - Thailand's finance ministry on Thursday slashed its 2021 economic growth forecast to 1.3%, from the 2.3% expansion it projected earlier, an official said, as the country struggles with its biggest COVID-19 outbreak to date.

However, the ministry raised its 2021 forecast for exports, a key growth driver, to a 16.6% rise from the 11% increase it predicted in April, Kulaya Tantitemit, head of the ministry's fiscal policy office, told a briefing. (Reporting by Orathai Sriring, Kitiphong Thaichareon and Satawasin Staporncharnchai Editing by Ed Davies)