The Melbourne Symphony Orchestra (MSO) has cancelled an acclaimed pianist's upcoming recital after comments he made on the Israel-Gaza war.

Jayson Gillham premiered Witness at a show at the MSO on Sunday. The piece was penned by another composer as a tribute to the Palestinian press.

The British-Australian was scheduled to perform again on Thursday, but the MSO has said it is reworking the programme after Gillham introduced the piece by saying Israel had killed more than 100 journalists.

A spokesperson for Gillham told the ABC he won't comment on the decision to drop him "out of respect to the MSO and his ongoing relationship with them".

Gillham - who is billed on the MSO website as "as one of the finest pianists of his generation" - was born in Australia but lives in the UK.

At the concert at the Iwaki Auditorium on Sunday, he performed a range of works, from Beethoven to Chopin. He also played Witness, written by Australian composer Connor D'Netto, which the MSO says was a last-minute addition.

"Over the last 10 months, Israel has killed more than 100 Palestinian journalists," Mr Gillham said before starting the piece.

A number were "targeted assassinations of prominent journalists" who were travelling in marked press vehicles or wearing press jackets, he claimed.

"The killing of journalists is a war crime in international law, and it is done in an effort to prevent the documentation and broadcasting of war crimes to the world," he added.

In an email to patrons, the MSO said they were blindsided by Mr Gillham's comments and he had put them in a "difficult situation".

“The MSO does not condone the use of our stage as a platform for expressing personal views”, it added.

Hamas-led gunmen killed about 1,200 people in an attack on Israel on 7 October, taking 251 others back to Gaza as hostages.

That attack triggered a massive Israeli military offensive on Gaza and the current war.

More than 39,790 Palestinians have been killed in the Israeli campaign, according to Gaza's Hamas-run health ministry.

The Committee to Protect Journalists, an independent organisation that promotes press freedom, reports that 113 of those were journalists.

Apologising for the "offence and distress" caused, the MSO said it had removed Gillham from the program and would update customers soon.

In a statement given to local media, a spokesperson for the MSO said: "Mr Gillham's remarks went beyond the remit of his contract."

The decision has caused a backlash on social media. High-profile barrister Greg Barns said the cancellation was “truly appalling” while art critics and former Sydney Symphony Orchestra chairman Leo Schofield said, “MSO management should hang its collective head in shame”.

The Israel-Gaza war has become a volatile political issue in Australia that all sides have sought to carefully manage.

As has been the case in countless other countries, there have been protests from both Jewish and Muslim communities, as well as a sharp uptick in Islamophobia and antisemitism.