"I am deeply distressed and brokenhearted by the massacre perpetrated by the State of Israel in Gaza yesterday", Tutu, a stalwart of South Africa's fight against racial inequality, said in a statement.
Belgium's foreign ministry said it summoned ambassador Simona Frankel over her remarks while Prime Minister Charles Michel said: "We call for an global inquiry led by the United Nations".
Ireland, according to Coveney's spokesperson, is also "very disturbed" by the level of injuries suffered by health workers tending to the injured, as reported by the World Health Organisation.
Tens of thousands of Palestinians attended Hamas-organized protests on the Gaza border and hundreds of others clashed with Israeli troops on the outskirts of Jerusalem and in other locations in the West Bank, marking the 70th anniversary of what they call the Nakba, or "catastrophe", of Israel's creation in 1948, as well as protesting the relocation of the USA embassy to Israel's capital on Monday afternoon.
The minister also summoned Israeli Ambassador Ze'ev Boker to a meeting on Tuesday to express his "shock and dismay" at Monday's events, TheJournal reports. "Israel is facing a real danger with the incitement by Hamas of its own population to storm the security fence and attack Israeli civilians".
"Fifty eight people have been killed as a result of the actions of Israeli forces; including six children and more than 2,700 have been injured".
"We continue to implore Israel to show greater restraint", he said.
Irish people on social media called Coveney out for taking a different tack in his treatment of the Russian diplomat, suggesting the Irish government is happy to follow Britain's orders but will fail to act on "crimes against humanity".
The Belgian leaders seemed to link the violence to Donald Trump's decision to move the embassy to Jerusalem, saying that it had "brought us further away from peace". "We stand in solidarity with the people of Palestine but words alone are not enough".
Fresh protests are expected today as Palestinians mark the Nakba, or "catastrophe", commemorating the more than 700,000 Palestinians who fled or were expelled in the 1948 war surrounding Israel's creation.
The death toll led to strong condemnation from rights groups and concern from a range of countries. This step by the Trump administration was controversial because it broke with decades of U.S. policy and infuriated Palestinians.