Israel has reopened its embassy in Cairo after a four-year hiatus, marking a new step in the further increase in cooperation between the two countries.

Israel and Egypt have shared diplomatic relations since signing a 1979 peace treaty. However, Israel’s embassy in Cairo was stormed by thousands of protestors and eventually evacuated in 2011 during the height of the “Arab Spring” and half-a-year after Hosni Mubarak was overthrown. Thousands of protesters stormed the embassy, using light poles as battering rams to demolish a protective wall around the compound.

Six security guards took refuge in a safe room in the embassy, and were finally evacuated hours later by Egyptian commandos, following direct intervention from US President Barack Obama.

A skeletal staff returned to Egypt, working out of the ambassador’s residence. Bilateral relations have since improved significantly under the rule of President Abdel Fattah el-Sisi, who overthrew the Muslim Brotherhood in 2014.

Israeli officials say they enjoy a robust relationship with the Egyptian government. “It’s going on for a while,” said the Israeli ambassador, Haim Koren, after a ceremony inaugurating the new embassy in what had been the ambassador’s residence.

“Especially on security issues, the cooperation is coming much better now. This is an opportunity, not in every single thing, but in a few things, and we have a common interest now.”

Dore Gold, the Director General of Israel’s foreign ministry flew to Cairo and rededicated the new Israeli embassy. He said that Israel’s Prime Minister Benjamin Netanyahu and Egypt’s President Fattah al-Sisi have succeeded in “deflecting the threat, and we are working together for the sake of stability and prosperity in the Middle East.” He added that Egypt “will always be the biggest and most important state in the region.”

The ceremony was also attended by a senior official from Egypt’s foreign ministry and the US Ambassador to Egypt.

A statement put out by the Foreign Ministry in Jerusalem said that, on the eve of Rosh Hashana, the beginning of a new year, “this event taking place in Cairo is also the beginning of something new.”

Israel’s Deputy Foreign Minister Tzipi Hotovely said that the reopening of the embassy will likely “elevate the relations between our two countries.” She added, “Against the background of regional developments, many opportunities present themselves for cooperation and an enhancement of relations between Israel and states in the region, especially Egypt.”

The warming in relations is partly predicated on cooperation on security. In the Sinai Peninsula, Egypt’s military is battling Islamic State-allied insurgents who have killed many Egyptian soldiers and police officers. Sinai-based terrorists have also fired into Israel, bombed a tourist bus and sabotaged a gas pipeline to Israel.

Egypt is trying to sever smuggling tunnels from Sinai into the Hamas-controlled Gaza Strip.

Egypt’s army announced this week that it had launched a “major military operation” against the ISIS affiliate in the Sinai Peninsula, saying that it had already killed 56 jihadists from the Sinai Province group, which has routinely attacked Egyptian troops and officials during a long-lasting campaign.

Israel and Egypt are thought to closely cooperate with regards to unrest in Sinai. Israel has permitted additional Egyptian forces in the region, despite limits set by the 1979 peace treaty

by Maureen Shamee