Rejecting the calls for a boycott, Mr Tennant wrote on the band’s website: “I don't agree with this comparison of Israel to apartheid-era South Africa. It's a caricature.
“Israel has (in my opinion) some crude and cruel policies based on defence; it also has universal suffrage and equality of rights for all its citizens both Jewish and Arab.
“In apartheid-era South Africa, artists could only play to segregated audiences; in Israel anyone who buys a ticket can attend a concert.”
The duo have regularly joined gay rights campaigns and supported other human rights issues.
Activists from the anti-Israel group Innovative Minds plan to picket a Pet Shop Boys appearance at a film screening on London’s Southbank on Wednesday evening.
Innovative Minds had asked the performers to “open their eyes to the ugly reality of apartheid Israel, to cancel their concert and stand with the oppressed Palestinians”.