Italian Prime Minister Giorgia Meloni has told a flotilla sailing towards Gaza to stop, saying the latest attempt by activists to deliver aid risks derailing a US plan to end the war.


More than 40 boats sailing in the Global Sumud Flotilla (GSF) have been accompanied by an Italian naval frigate, which Italian officials said would stop once the flotilla was 150 nautical miles (278km) from Gaza's shoreline.


Shortly after reaching that point on Wednesday, GSF said it was on high alert and that drone activity was increasing above the flotilla.


Meloni said the US proposal had sparked hope of ending the Israel-Hamas war, adding it was a fragile balance, which many would be happy to destroy.


I fear that the flotilla's attempt to break the Israeli naval blockade could serve as a pretext to do so, Meloni said.


Israel has told the flotilla to deliver the humanitarian aid to an Israeli port instead, according to the AFP news agency.


The flotilla consists of more than 500 people, including Italian politicians and Swedish climate activist Greta Thunberg.


In a series of posts on Telegram early on Wednesday morning, GSF said that it has now entered the area where previous flotillas have been attacked and/or intercepted.


It added that they had prepared for a possible interception after several unidentified vessels, some without lights, approached the flotilla. The unidentified vessels have since departed.


Italian officials have urged the flotilla to accept a compromise and drop the aid in Cyprus to avoid a confrontation with Israel.


Any other choice risks becoming a pretext for preventing peace, fuelling conflict and therefore affecting above all the people of Gaza, Meloni said.


But in a statement, the Global Sumud Flotilla said it would continue to sail.


The Italian navy will not derail this mission. The humanitarian demand to break the blockade cannot be walked back to port, it said.