Seoul (AFP)

South Korea's President Yoon Suk Yeol on Tuesday declared emergency martial law, accusing the opposition of being "anti-state forces intent on overthrowing the regime" amid parliamentary wrangling over a budget bill.

"To safeguard a liberal South Korea from the threats posed by North Korea's communist forces and to eliminate anti-state elements plundering people's freedom and happiness, I hereby declare emergency martial law," Yoon said in a live televised address to the nation.

"With no regard for the livelihoods of the people, the opposition party has paralysed governance solely for the sake of impeachments, special investigations, and shielding their leader from justice," he added.

The surprise move comes as Yoon's People Power Party and the main opposition Democratic Party continue to bicker over next year's budget bill. Opposition MPs approved a significantly downsized budget plan through a parliamentary committee last week.

The opposition has slashed approximately 4.1 trillion won ($2.8 billion) from Yoon's proposed 677 trillion won budget plan, cutting the government's reserve fund and activity budgets for Yoon's office, the prosecution, police and the state audit agency.