Pharrell Williams, a ten-time Grammy Award winner, has canceled his 21 July performance in Tel Aviv amid conflicting explanations.

Over the last year, the “Happy” pop star has faced sustained pressure from the Palestine solidarity movement. Last year, amid rumors that he would be scheduling a Tel Aviv performance, campaigners urged him not to go.

In an open letter, the US Campaign for the Academic and Cultural Boycott of Israel said that by performing in Tel Aviv, Williams would show himself “indifferent to the suffering of Palestinian children.”

The cancellation also comes as other big names, including Carlos Santana, are being urged by fans not to “entertain apartheid” by performing at Israeli venues.

Israeli media have provided conflicting explanations for Pharrell’s Tel Aviv no-show.

The newspaper Haaretz cited lackluster ticket sales, while The Jerusalem Post reported “scheduling conflicts.”

BDS South Africa has made Williams a focus of its campaigning over his endorsement of the retail chain Woolworths, because of its sales of Israeli goods.

Last September, an effort to limit the size of a Palestine solidarity protest outside the Cape Town venue where Williams was perfoming was thrown out by a South African judge.