Activists on a flotilla which is trying to breach Israel’s naval blockade and deliver aid to Gaza say they are back on course after a reported confrontation with an Israeli warship in the early hours of Wednesday.

The Global Sumud Flotilla (GSF) says that one of its lead vessels, Alma, was “aggressively circled” by an Israeli warship for several minutes, and on board communications were cut off during the incident.

The Israeli boat forced Alma’s captain to take evasive manoeuvres, activists say, before the same vessel repeated what activists described as “harassing manoeuvres” on another boat.

Israel has previously said it will not let the flotilla reach its destination.

It has already blocked two attempts by activists to deliver aid by ship to Gaza, in June and July.

The latest Gaza-bound grouping consists of more than 40 boats and 500 people, including Italian politicians and Swedish climate activist Greta Thunberg.

Thiago Avila, who is on the Alma, said the boat’s devices were disabled during the incident, affecting cameras, livestreams and communication systems.

Lisi Proenca, who is on Sirius – the second GSF ship involved – said the Israeli vessel circled for about 15 minutes and that their communications were also affected.

Activists had earlier said they had prepared for a possible interception after several unidentified vessels, some without lights, approached the flotilla in an area “where previous flotillas have been attacked and/or intercepted”.

The boats sailing in the flotilla had been accompanied by an Italian naval frigate, but Italian officials said that it would stop once the flotilla was 150 nautical miles (278km) from Gaza’s shoreline.

As of Wednesday afternoon, the GSF said its boats were 100 nautical miles from Gaza.

Previous flotillas have been intercepted by Israeli forces around that point.

However, a former Israeli naval intelligence chief told BBC Verify that Israel’s military may wait until the vessels are closer to the coast due to the presence of ships from other navies.

“If I was the decision maker, I would engage them inside Israeli territorial waters in order to avoid escalation,” Eyal Pinko said.

“The Israeli navy has the full intention and the full will not to escalate with friendly navies and those who are on the ships.”

Italy and Greece have called on Israel to ensure the safety and security of the activists and said they are closely monitoring developments.

The two countries also called on the activists to accept a compromise proposal to drop the aid in Cyprus and let the Catholic Church distribute it.

Their joint statement refers to the US Gaza peace plan, warning against initiatives that could be “exploited by those who still reject peace”.

Earlier, Italian Prime Minister Giorgia Meloni had urged the activists to stop the journey, saying their actions could serve as a pretext to those who want to destroy the “hope” of ending the conflict.

Israel’s Foreign Minister Gideon Saar noted the Italy-Greece statement and called on the flotilla to stop.

“Please transfer any aid you might have peacefully through the Port of Cyprus, [Israel’s] Ashkelon Marina, or any other port in the region into Gaza,” he wrote on X.

The GSF said in an earlier statement that it would continue to sail.

“The humanitarian demand to break the blockade cannot be walked back to port,” it said.

Last week, Italian Defence Minister Guido Crosetto condemned what he described as an overnight drone attack by unidentified perpetrators on the flotilla.

Italy and Spain deployed naval ships to escort the flotilla, then off the coast of Crete, after it reported explosions, drones overhead and communications jamming – accusing Israel of a “dangerous escalation”.

Israel did not comment on the incident – but has repeatedly said the flotilla is a Hamas operation, without citing evidence.

Pope Leo XIV also expressed concern for the safety of the flotilla. “From all sides, people are saying, ‘let’s hope that there will not be violence, that people are respected’. That’s very important,” he said.

Greta Thunberg pushed back against criticism that the flotilla was a publicity stunt, in an interview with the BBC on Sunday.

“I don’t think anyone would risk their life for a publicity stunt,” she said.

The US peace plan for Gaza proposes an immediate end to fighting, the release within 72 hours of 20 living Israeli hostages held by Hamas, as well as the remains of the more than two dozen hostages who are believed to be dead – in exchange for hundreds of detained Gazans.