The DA says it will lodge a complaint with parliament’s ethics committee after an EFF MP slapped a police officer at the state of the nation address (Sona).

"The MP is Mr Marshall Dlamini and his conduct is most unbecoming of a member of parliament - but hardly surprising as it fits in with the pattern of thuggery that the EFF has consistently displayed on the precinct‚" said DA chief whip John Steenhuisen.

"The DA will be lodging a complaint with the ethics committee in parliament as well as the powers and privileges committee to investigate the conduct of the MP concerned‚" he added.

In a widely circulated video‚ the EFF MP was seen slapping warrant officer Johan Carstens.

Parliament and the African Christian Democratic Party (ACDP) have condemned the incident.

National assembly speaker Baleka Mbete and National Council of Provinces chairperson Thandi Modise said they "denounce in the strongest terms the alleged assault of a police officer stationed at parliament".

ACDP MP Steve Swart described the incident as "disgraceful".

"It's illegal for them to slap someone‚" he said.