Debates over a new pension bill in Turkey's Grand National Assembly spiralled into chaos on Sunday, with lawmakers trading punches in a brawl that raged for nearly 10 minutes on the chamber floor.

Video footage shows MPs throwing fists as others crowded in, turning the parliamentary session into a violent scuffle.

According to local media, the confrontation erupted after a Republican People's Party (CHP) lawmaker carried a symbolic cardboard coffin to the podium, protesting pension increases the opposition says are insufficient for retirees to live on.

Tensions escalated when members of the ruling AK Party moved to seize the prop, triggering a mass fistfight that spread across the assembly hall.

Despite the turmoil and objections from some lawmakers, the bill to raise pensions to 20,000 lira (approximately $461) ultimately passed.