Egyptian authorities have detained more than 200 pro-Palestinian activists who arrived in Cairo by plane as part of a solidarity march to Gaza to push for increased humanitarian aid access to the enclave. A convoy that left Tunisia for Gaza is currently blocked in Libya.

"Over 200 participants were detained at Cairo airport or questioned at hotels across Cairo," the march's spokesperson, Saif Abukeshek, told France's AFP news agency on Thursday.

The detainees included people from Algeria, Australia, France, Morocco, the Netherlands, Spain and the United States, he said.

Plainclothes officers entered Cairo hotels on Wednesday with lists of names, questioning activists, and in some cases, confiscating phones and searching personal belongings, Abukeshek said.

"After interrogations, some were arrested and others were released."

More than 20 French activists who had planned to join [Friday's] march were held at Cairo airport for 18 hours, he said.

"What happened was completely unexpected," Abukeshek said.

Egyptian authorities said the measures were the result of failure to follow proper procedures, including obtaining prior consent from embassies and securing visas.

Cairo maintains that the march towards Rafah constitutes a threat to both its own security and that of the participants.

After 21 months of war, Israel is facing mounting international pressure to allow more aid into Gaza, which the United Nations has dubbed "the hungriest place on Earth".

In a statement, the organising collective said: “We hope we can work with the Egyptian authorities … Our priorities are the same – calling for an end to the Palestinian genocide.”

Egyptian authorities have also deployed reinforcements at its border with Libya to block a convoy of around 1,500 people that set out from Tunisia on Monday.

The caravan, dubbed Soumoud meaning "resiliance" in Arabic, left Tunis with the aim of reaching Gaza to symbolically “break the Israeli blockade”.

Around 1,500 people, including Algerian and Tunisian medics, activists and supporters, are travelling in a dozen buses and a hundred cars.

The convoy arrived in the Libyan capital Tripoli on Wednesday, but is currently blocked in Sirte in the centre-north of the country, which is under the control of forces led by Marshal Khalifa Hafta.

"The caravan was prevented from proceeding at the entrance to the city of Sirte,” said one of the organisers, Wael Naouar, in a video on Facebook.

“So far we do not know whether we will be able to continue or not,” Naouar added, while insisting they would not turn back.

The Global March to Gaza, which is coordinating with Soumoud, said around 4,000 participants from more than 40 countries are expected to take part in Friday's event.

According to the plan, participants are set to travel by bus to the city of El-Arish in the heavily secured Sinai Peninsula before walking 50 kilometres towards the border with Gaza.

Israel has called on Egyptian authorities "to prevent the arrival of jihadist protesters at the Egypt-Israel border".

Egypt's foreign ministry said that while it backs efforts to put "pressure on Israel", any foreign delegations visiting the border area must receive approval through official channels.

The Israeli army said on Wednesday that it had allowed 56 trucks carrying World Food Programme humanitarian aid to enter the north of Gaza.

Earlier this week, Israel intercepted a ship carrying Western pro-Palestinian activists and aid for Gaza.

The twelve activists aboard, including Swedish climate campaigner Greta Thunberg, were deported.

Rima Hassan, a French MEP from the hard-left France Unbowed (LFI) party who is of Palestinian descent, returned to France on Thursday evening having been held in solitary confinement in Israel.