Parti Sosialis Malaysia (PSM) will not help the opposition to campaign during the upcoming Kuala Kangsar by-elections if they end up with three-cornered fights.

"We said (to the other opposition parties) 'don't do three-cornered fights'.

"If they go against our suggestion, our advice, then we are not obliged to (help)," PSM leader Michael Jeyakumar Devaraj said in a press conference at the party headquarters in Brickfields today.