"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.
Albayrak aims to build four new berths and repair others, bringing the number of working berths to 10.
"I'm in Belgrade for the first time in 25 years," Hoxhaj told reporters, "It shows how difficult the journey was to come to Belgrade, (just) a four-hour drive up the road."
Event participants in Addis Ababa are expected to discuss various topics related to federalism, including fiscal federalism
Greek Cypriot leader Nicos Anastasiades was rushed to hospital after pro-longed nose bleed on Thursday but was later released.
A Tunisian policeman was killed on Thursday when security forces clashed with militants on the outskirts of Tunis
Japan's defence ministry has said an X-Band radar system was delivered on Tuesday to the U.S. military's communication facility in Kyoto in the western part of the country
Israeli police said on Twitter that a Palestinian man had been detained at a military checkpoint, one day after a Palestinian driver was killed for allegedly hitting several Israeli pedestrians
Media reports of a suspected Russian submarine in Swedish waters could pressure the country to spend more on its military, expert says
Khama's Botswana Democratic Party (BDP) is expected to win a reduced majority, extending the grip on power it has held since 1966
Some companies have threatened to halt operations and lay off workers if taxes are not refunded
A Muslim Brotherhood source said that Morsi, who faces multiple criminal charges, did not have a say in the matter since he refuses to recognize the legitimacy of the trials.
Troops repulse Bangsamoro fighters attack on civilian community, after 2 soldiers killed at hospital
The sources said the apartment in the northern town of Asoun housed Lebanese and Syrian gunmen wanted by authorities
Oxford-educated Bilawal Bhutto Zardari told Reuters that he planned a series of rallies in a challenge to Pakistan's embattled prime minister, Nawaz Sharif.
The detainees were moved to detention centers run by the internal security agency (Shin Bet) for interrogation
Student leader says can’t see any ‘practical need’ for second round of talks on political reform after first meeting Tuesday