National Assembly Speaker Kim Jin-pyo criticizes the president's bodyguards' physical restraint of a minor opposition lawmaker last week during a plenary session held at the National Assembly in Seoul on Thursday. (Yonhap)

National Assembly Speaker Kim Jin-pyo on Thursday criticized the president's bodyguards' use of force against a minor party lawmaker at a recent event.

Calling the restraint "excessive," he warned that such actions should not be repeated and called for the Cabinet and the parliament to have mutual respect.

"Appropriate solutions must be adopted, to prevent such excessive measures from the president's bodyguards," Kim said during a speech at Thursday's plenary session held at the National Assembly in Seoul.

Rep. Kang Sung-hee of the progressive Jinbo Party was dragged out of a venue last week in Jeonju, Jeonbuk State, after telling Yoon to change his policies in person.

The president's four bodyguards physically removed him after viewing him "as a threat to Yoon's security," according to a source at the presidential office who declined to be named. The official explained that Kang did not let go of Yoon after a handshake, and continued shouting at the president.

Kim continued his speech despite receiving several verbal protests from the ruling People Power Party lawmakers.

"The Assembly needs to treat the Cabinet with manners and the government needs to have respect for the Assembly," he added.

Kim's remarks came as the conservative bloc's efforts to pass a bill to delay a wider implementation of the Serious Accidents Punishment Act, which aims to punish employers who failed to prevent fatal workplace accidents, fell through during the plenary session.

But the opposition-led Assembly passed a bill that allows temporary suspension of the statute of limitations for defendants who flee overseas during a trial. The bill aims to reform the current Criminal Procedure Act which allows the statute of limitations to expire even if a defendant manages to flee overseas before a verdict is reached.

A bill to support the construction of a 6 trillion won ($4.48 billion) railway project connecting several cities located between Daegu and Gwangju was passed as well. The project, called the "moonlight railway" in Korean, seeks to build 200 kilometer rail line by 2030.