Israel faced a growing backlash Tuesday as Belgium and Ireland joins countries who summoned Israeli ambassadors over the killings of 61 Palestinians and more than 2,700 injuries along the Gaza border.

Belgium's foreign ministry said it summoned ambassador Simona Frankel over her remarks while Prime Minister Charles Michel said: "We call for an international inquiry led by the United Nations."

Ireland also summoned the Israeli ambassador "to express the government and the people's outrage and dismay" at the deaths of dozens of protesters in Gaza, Prime Minister Leo Varadkar said.

Varadkar said the government was "profoundly shocked at the death toll and the scale of injuries that have been inflicted by Israeli forces on Palestinian demonstrators."

He called for an "independent, international investigation" into the bloody protests on Monday on the border with Israel.

"There's no indication that the scale of the threat could have justified such violence and so many deaths," Varadkar said in the Irish parliament.

Thousands of Palestinians have gathered on Gaza Strip's eastern border since Monday morning to take part in demonstrations aimed to commemorate the Nakba anniversary and protest relocating of the U.S. Embassy from Tel Aviv to Jerusalem.

According to the Palestinian Health Ministry, at least 60 Palestinian demonstrators have been martyred by cross-border Israeli gunfire in one of the deadliest single day massacres in the country's history.