EU chief Ursula von der Leyen said on Wednesday that the Palestinian group Hamas's killing of Israeli civilians was a cold-blooded act of war and reflected an "ancient evil".
"We have to be clear in defining this kind of horror," she said. "And there can only be one response to it. Europe stands with Israel. And we fully support Israel's right to defend itself."
Addressing the start of a meeting of European commissioners, von der Leyen also supported a full review of the EU's multi-million-euro financial support for Palestinian projects.
On Saturday, Hamas attacked Israel's border around the Gaza enclave and launched attacks on civilian and military targets, leaving more than 1,200 dead.
Israel has responded with artillery and air strikes, and Gaza officials estimate more than 900 Palestinians dead after five days of ferocious fighting.
The EU and its member states have responded with expressions of solidarity with Israel and furious disgust at Hamas's assault. "It is terrorism. And it is an act of war," von der Leyen said.
But they are also concerned that Israel keeps its response within the limits of international law.
"Hamas terrorists killed women and children in their homes. They hunted hundreds of young men and women who were celebrating life and music," von der Leyen told the European Commission.
"They took hostage hundreds of innocents, whose fate is still unknown," she said.
"These innocents were killed for one single reason: For being Jewish and living in the State of Israel. It is an ancient evil, which reminds us of the darkest past and shocks all of us to the core."
Von der Leyen also addressed a debate raging in Brussels over the European Union's huge budget to support the Palestinian Authority and state-building projects in Palestinian territories.
The EU commissioner in charge of relations with Europe's neighbours, Hungary's Oliver Varhelyi, has called for aid to be suspended pending a review of whether any leaked to armed groups like Hamas.
But EU foreign policy chief Josep Borrell, with the backing of most member state foreign ministers, wants funding to continue while any review is carried out to avoid punishing Palestinian civilians.
"Our humanitarian support to the Palestinian people is not in question. Yet it is important that we carefully review our financial assistance for Palestine," von der Leyen said.
"EU funding has never and will never go to Hamas or any terrorist entity. So we will now again review the entire portfolio in light of an evolving situation on the ground."
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
