[attach id=237052 size="medium"]Palestinians repairing a smuggling tunnel flooded by Egyptian forces, beneath the Egyptian-Gaza border in Rafah, in the southern Gaza Strip. Photo: Reuters[/attach]

Egypt will not tolerate a two-way flow of smuggled arms with the Gaza Strip that is destabilising its Sinai peninsula, a senior aide to its Islamist President said, explaining why Egyptian forces flooded sub-border tunnels last week.

The network of tunnels has been a lifeline for some 1.7 million Palestinians in Gaza, bringing in an estimated 30 per cent of all goods that reach the enclave and circumventing a blockade imposed by Israel for more than seven years.

But Essam Haddad, national security adviser to President Mohamed Morsi said in an interview: “We don’t want to see these tunnels used for illegal ways of smuggling either people or weapons that can really harm Egyptian security.”

He said that under a deal brokered by Cairo to end fighting in November between Israel and the Hamas movement that rules the Gaza Strip, the Israeli stranglehold on the coastal territory had been considerably relaxed. Egypt has eased border controls to allow in construction materials, notably from Qatar.

“Now we can say that the borders are open to a good extent – it could still be improved – and the needs of the Gazan people are allowed in. Building materials are allowed in for the first time,” Haddad said.

Sixteen Egyptian border guards were killed last August in a militant attack in Sinai near the Gaza fence that shocked Egyptians and highlighted lawlessness in the desert region adjoining Israel and the Gaza Strip.

Cairo said some of those gunmen had crossed into Egypt via the Gaza tunnels – an accusation denied by the Palestinians. Dozens of tunnels have been destroyed since that incident.