Cairo: Egypt will permanently open the Rafah border crossing to ease the blockade on Gaza, Foreign Minister Nabil Al Arabi said Friday, sparking Israeli concerns over the implications for regional security.

Arabi said in an interview with Al Jazeera his country would take "important steps to help ease the blockade on Gaza in the few days to come," according to the Arabic-language satellite channel.

He said Egypt would no longer accept that the Rafah border - Gaza's only crossing that bypasses Israel - remain blocked, describing his country's decision to seal it off as "shameful."

In occupied Jerusalem, a senior Israeli official said the Jewish state is "very concerned" about the implications of the Rafah crossing being thrown open.

Speaking on condition of anonymity, the Israeli official said Gaza's Hamas rulers had already build up a "dangerous military machine" in northern Sinai which could be further strengthened by opening the border. "We are troubled by the developments in Egypt, by the voices calling to annul the peace treaty, by the rapprochement between Egypt and Iran, and by the upgrading of relations between Egypt and Hamas. These developments potentially have strategic implications for Israel's national security."

Egypt has largely kept Rafah closed, opening it exceptionally for humanitarian cases from the besieged Gaza Strip.

Israel imposed its blockade on Gaza in 2006, further tightening it the following year when the Islamist Hamas movement seized control of the territory from forces loyal to Western-backed Palestinian president Mahmoud Abbas.

Since 2007, Gaza's 1.5 million people have relied on a web of tunnels beneath the Rafah border for most of their needs.

A 2005 agreement brokered by the United States put the Palestinian Authority and Israel in charge of Rafah, with observation from the European Union.