A South Korean high court has extended the lengthy prison sentence of former President Park Geun-hye for corruption in office.

In April, a district court sentenced Park to 24 years in jail over bribery, extortion, abuse of power and other charges. She was removed from office last year following months of street rallies over the corruption scandal.

The Seoul High Court on Friday handed out a 25-year prison sentence after concluding Park took more money in bribes than initially believed.

Park, daughter of late dictator Park Chung-hee, was South Korea's first female president. She has called herself a victim of political revenge.