Israeli Prime Minister Benjamin Netanyahu on Sunday denounced six new European members of a barter mechanism with Iran, saying it encouraged Tehran's repression of protests.
"While the Iranian regime is killing its own people, European countries rush to support that very murderous regime," the embattled leader said in a statement.
"These European countries should be ashamed of themselves."
Protests broke out across sanctions-hit Iran on November 15, hours after a sharp fuel price hike was announced.
Reports of deaths and arrests emerged as security forces were deployed to rein in demonstrations which turned violent in some areas, with dozens of banks, petrol garages and police stations torched.
London-based human rights group Amnesty International has said 161 demonstrators were killed.
"Belgium, Denmark, Finland, the Netherlands, Norway, and Sweden could not have picked worse timing," said an English-language statement from the Israeli foreign ministry.
"The hundreds of innocent Iranians murdered during the latest round of protests are rolling in their graves."
A 2015 international agreement set out restrictions on Iran's nuclear programme in exchange for the lifting of Western sanctions.
The Paris-based INSTEX functions as a clearing house allowing Iran to continue to sell oil and import other products or services in exchange.
The system has not yet enabled any transactions.
Last year Washington unilaterally withdrew from the deal and reinstated crippling sanctions against Tehran.
Israel, which accuses the Islamic republic of seeking to acquire nuclear weapons, vigorously opposed the 2015 pact and is lobbying for more sanctions, not fewer.
"We ask these European countries -- what message are you sending to the Iranian people?" the foreign ministry statement said.
"Would it not be more effective and ethical to designate the regime officials responsible for the murder of innocent civilians?"