"There is no justification for the closure of the Rafah crossing," Hamad al-Raqb, a spokesman for the protesters, said in a speech marking the beginning of a four-day sit-in.
"It is unbecoming of the historic relations between Egyptians and Palestinians," he insisted.
Leading Hamas figures and MPs attended the launch ceremony.
Egyptian authorities have tightened their control over the border with the Hamas-run Gaza Strip since last July's ouster of elected president Mohamed Morsi by the Egyptian army.
In recent weeks, Egypt has repeatedly closed the Rafah crossing, which – due to an ongoing, eight-year Israeli siege – represents Gaza's only window to the outside world.
The Egyptian army has also launched a campaign aimed at destroying the network of tunnels linking Gaza to Egypt's Sinai Peninsula, which in recent years had been used to bring vital commodities into the besieged coastal enclave, home to nearly 2 million Palestinians.
Hamas, an ideological offshoot of the Muslim Brotherhood, the group which propelled Morsi to power in the 2012 elections, has controlled the Gaza Strip, since 2007.
Afghanistan's highest court has ruled that the police officer convicted of murdering Associated Press photographer Anja Niedringhaus should serve 20 years in prison
The country's ambassador to the United States told NBC on Sunday morning, Saudi Arabia is focussing on using air strikes.
Egypt lists 17 Brotherhood leaders including the former leader of the Muslim Brotherhood Mohamed Mahdi Akef and the head of the Brotherhood's Freedom and Justice Party Saad al-Katatni, as 'terrorist' figures
According to Independent news, foreign students banned from British university science lessons on the gorunds that they might learn how to make nuclear and chemical weapons
Saudi Arabia accused Russian President Vladimir Putin of hypocrisy on Sunday, telling an Arab summit that he should not express support for the Middle East while fuelling instability by supporting Syrian leader Bashar al-Assad.
The march headed towards the museum where a memorial for the victims of the attack will be inaugurated
Slovenian President Borut Pahor has said ahead of President Recep Tayyip Erdogan's official visit Monday, Slovenia supports Turkey's EU membership
Arab leaders said Saudi-led operation would continue until the Iranian-allied Houthis withdraw. They also announced the formation of a unified military force to counter growing security threats from Yemen to Libya.
Collation of results continues and final results are not expected until Monday
Tens of thousands of Tunisians marched through the capital in a show of solidarity against museum attack on Sunday, hours after the government said its forces had killed nine members of a group suspected of carrying out this month's Bardo Museum attack.
According a port official, a Chinese warship approach the port of Aden to evacuate nationals.
An Israeli court has issued an order to demolish Palestinian village Susya and relocate its residents. The village was built even before the Israeli occupation of the West Bank in 1967.
At least 15 people wounded from anti-aircraft missiles shrapnel used by Houthis against warplanes of the Saudi-led coalition in Western Yemen
According to a Yemeni NGO Mwatana Organization for Human Rights (MOHR), at least 27 civilians – including 15 children – were killed in Yemen's Sanaa province.
Yemeni President Abd-Rabbu Mansour Hadi has fired Ahmed Ali Saleh who is son of former president Ali Abdullah Saleh.
Tunisian security forces have killed a senior Algerian suspected who they accuse of helping orchestrate the Bardo museum attack which targeted foreign tourists, Tunisia's Prime Minister Habib Essid said on Sunday.