"I don't think Netanyahu is exactly the person entitled to lecture anyone while committing the atrocities he is committing in Gaza," Spanish defence minister Margarita Robles told Antena 3 television.
Her comments came in reaction to a message Netanyahu's office posted on X Thursday accusing Sánchez of threatening Israel -- the latest fiery exchange between the two countries.
On Monday, the Spanish premier had announced measures to "put an end to the genocide in Gaza", including an arms embargo, a ban on boats carrying fuel for the Israeli military and restrictions on imports from illegal settlements.
"Spain, as you know, does not have nuclear bombs. Nor does it have aircraft carriers or large oil reserves. We alone cannot stop the Israeli offensive, but that does not mean we will stop trying," he said in an address.
On Thursday, Netanyahu's office issued a scathing response.
"Spanish PM Sánchez said yesterday that Spain can't stop Israel's battle against Hamas terrorists because 'Spain does not have nuclear weapons.' That's a blatant genocidal threat on the world's only Jewish State," it said.
A few hours later, Spain's foreign ministry issued a rebuttal.
In a statement, it stressed that "the Spanish people are friends of the people of Israel as of the people of Palestine", denouncing the Israeli premier's remarks as "false and slanderous".
The week-long spat between Israel and Spain comes after months of worsening relations.
Socialist leader Sánchez has been one of Europe's most vocal critics of Israel's military campaign in Gaza, launched after the unprecedented October 7, 2023 Hamas attack on Israeli soil.
He is the most senior European leader to refer to the war as a "genocide", and in May of last year broke with European allies by recognising a Palestinian state.
Israel has since had no ambassador in Madrid, which recalled its own ambassador to Israel on Monday after Foreign Minister Gideon Saar accused Spain of waging an "anti-Israel and antisemitic campaign".
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