ISMAILIA, EGYPT/GAZA (Reuters) – Egypt reopened the Rafah border crossing with Gaza on Saturday, a lifeline for Gazans which had been closed for much of the month since an August 5 attack on Egyptian guards, Palestinian and Egyptian security sources said.

The move signals an advance in relations between Egypt’s new government lead by President Mohammed Mursi and Gaza’s Islamist rulers Hamas, which had deteriorated since the attack in which gunmen killed 16 Egyptian soldiers on the Israeli border.

“The Egyptian side has informed us that the Rafah crossing would open all days of the week, without more details,” said Ehab Al-Ghsain, spokesman for the interior ministry in Gaza.

The opening of the crossing was confirmed by an Egyptian security source.

Shortly after the attack, Egypt closed the Rafah crossing and moved to seal myriad smuggling tunnels with Gaza on suspicion they might have been used by militants who shot dead the soldiers before storming an Israeli border crossing near Gaza. The attackers were killed by Israeli fire.

The Rafah crossing normally sees some 800 people a day leave for Egypt and beyond, and is the only window on the world for the vast majority of Gazans.

Egypt later said it would open the crossing temporarily, but just for three days, mainly to permit travel for humanitarian purposes such as Palestinians seeking medical care abroad.

Hamas has ruled out suggestions that Palestinian gunmen took part in the Sinai killings and has criticised Cairo for imposing “collective punishment” on the impoverished Mediterranean coastal enclave by sealing the border.

Hamas hoped the election of the Muslim Brotherhood’s Mursi would usher in an era of strong ties between Gaza and Cairo, but that has yet to materialise because of strategic considerations involving Egypt’s 1979 peace treaty with Israel and related military aid from the United States.