The chant was heard at the Madejski Stadium as Chelsea beat Reading 4-3 in a friendly on Monday (AEST), prompting Lampard to remind his side's fans of the work the club has done to combat prejudice.

The use of the word "pikeys" to refer to West Ham is considered a slur as historically it has been used as a term of abuse against traveller communities including the Romani.

Chelsea supporters were condemned by anti-racism campaign group Kick It Out last season after chants directed at Mohamed Salah, while four fans were suspended during investigations into the alleged racial abuse of Manchester City's Raheem Sterling at Stamford Bridge.

Lampard said he didn't hear the "pikeys" song, but said: "If there's a song in the modern day or any day that has offensive words, I don't want to hear that.

"That's me saying that as a big Chelsea man who really appreciates the support I've had over the years. We don't want songs with offensive words. If the fans could sing other songs then I'll back that. We don't want to hear that.

"The club are very clear with the work we do off the pitch about anything that's offensive or prejudiced and we've made a big mark on that."

Callum Hudson-Odoi, who has missed Chelsea's pre-season preparations while recovering from surgery on his Achilles tendon, is reportedly close to signing a new contract at Stamford Bridge.

Asked whether a deal had been agreed for Bayern Munich target Hudson-Odoi, Lampard said: "I think agreed would mean signed so we're not quite there but what's very clear is the club are working towards that.

"Talks moved on very well in the last week or two but it's not done yet. The one thing that's clear to me is I want to keep him here.

"He's a player we cherish. Players who come through the academy are the present and the future of the club so we're doing everything we can to get there. I hope it's news to be confirmed soon."

Hudson-Odoi made 10 Premier League appearances last season, but Lampard indicated the teenager may struggle to be fit to face Manchester United on August 11.

"There will be a period for Callum where his injury is fine and then he needs to get fit to play in this team because it will be demanding with the way I want to play, from front to back," said Lampard.

"He's not far away and I know he's done everything he can to be fit through the summer and the medical team have been very good. We're getting close."