Turkish President Recep Tayyip Erdogan on Saturday condemned Israel over its “inhumane attack” in Gaza after a major demonstration there led to clashes that saw Israeli forces kill 16 Palestinians.

The violence broke out on Friday after tens of thousands of people in the Gaza Strip marched near the Israeli border.

Over 1,400 people were also wounded, 758 of them by live fire, with the remainder hurt by rubber bullets and tear gas inhalation, the Gazan health ministry said.

“I strongly condemn the Israeli government over its inhumane attack,” Erdogan said during a speech in Istanbul.

The protesters were demanding hundreds of thousands of Palestinian refugees who fled or were expelled during the war surrounding Israel's creation in 1948 be allowed to return.

“Have you heard any noteworthy objections to the massacre by Israel that happened yesterday in Gaza from those who criticise the Afrin operation?” Erdogan demanded.

Turkey on January 20 launched a cross-border operation against the Kurdish People's Protection Units (YPG) in its enclave of Afrin and the city was captured on March 18.

Ankara has come under heavy criticism from opponents and activists over its own operations in northern Syria.

“This is the biggest proof of insincerity of those who fixate on us but say nothing about Israel using heavy weapons to attack people who are protesting on their own lands,” Erdogan said, without saying which governments and organisations he meant.

Erdogan on Friday spoke with US President Donald Trump in a call and the Turkish leader said he told Trump: “'Aren't you going to intervene here?”.

The Turkish leader, a fervent supporter of the Palestinians, often criticises Israel's policies but the two sides have increased cooperation since the end of a rift in 2016 caused by Israel's storming in 2010 of a Gaza-bound ship that left 10 Turkish activists dead.

The Turkish foreign ministry on Friday accused Israel of using “disproportionate force” against Palestinians during “peaceful protests”.