The Coldplay frontman vented about the "completely insane" traffic during his gig at Bulacan's Philippine Arena ... hilariously singing: "There is only really one thing that remains. The traffic here in Manila is completely insane."

Watch in the clip ... Chris gripes about a 2-mile drive taking a week or two ... and people should allow themselves a year and a half to get home in time for a bath.

The audience was laughing at each line, but maybe just to avoid crying about their traffic plight ... as Chris hit the chorus, "Oh, we can't wait to play Manila again, but the traffic here is completely insane."

Fun and games aside, Manila's traffic problem has been a real issue ... with the city topping the 2023 TomTom Traffic Index list of metro areas with the slowest travel time of almost 400 cities in 55 countries.

The Department of Transport in the Philippines says it's fast-tracking road projects aimed at "improving commuter experience while addressing worsening traffic in highly urbanized areas."

Although, the government's well aware of its crappy traffic numbers, Philippine President Ferdinand Marcos Jr. was criticized for using public funds to arrive at Coldplay's concert Friday via helicopter, rather than using its own public transport.

So, it looks like there's some miscommunication over how best to navigate the issue.