UK Labour Party leader Jeremy Corbyn has urged the government of Prime Minister Theresa may to take action against Israel’s “slaughter” of Palestinian anti-occupation protesters in Gaza.

“Today’s killing of dozens of unarmed protesters and the wounding of many more by Israeli forces in Gaza is an outrage that demands not just international condemnation, but action to hold those responsible to account,” Corbyn said in a Facebook statement on Monday.

“This slaughter follows weeks of killings of Palestinian civilians demonstrating for their right to return, most of whom are refugees or the families of refugees,” Corbyn said.

The remarks came after Israeli military forces opened fire on thousands of Gazans, who had gathered on the border with Israel to protest the opening of a new US embassy in Jerusalem al-Quds.

The violence saw Israeli troops kill 59 people and injure over 2,700 more by targeting them indiscriminately.

Protests in the coastal strip started as the “Great March of Return” in late March and have been regularly held over the past seven Fridays. The rallies will culminate on the 70th anniversary of the Nakba Day (Day of Catastrophe), which marks the creation of Israel on May 14, 1948.

“The response from many western governments to this flagrant illegality, including our own - which bears a particular responsibility for a peaceful and just resolution of the Israel-Palestine conflict - has been wholly inadequate,” Corbyn said.

He said London should address Israel’s “multiple abuses of human and political rights Palestinians face on a daily basis, the 11-year siege of Gaza, the continuing 50-year occupation of Palestinian territory and the ongoing expansion of illegal settlements.

“We cannot turn a blind eye to such wanton disregard for international law,” he continued.

Corbyn also pledged to review Britain’s arms sales to Israel once he becomes prime minister.

Trump’s decision to move the US diplomatic mission to the ancient city has been met with outrage among Palestinians, who deem Jerusalem al-Quds as the future capital of a Palestinian state.

The opening ceremony, held amid tightened security measures, was attended by Trump’s daughter, Ivanka, and his son-in-law, Jared Kushner. Trump addressed the event in a video message.