Egypt has been sending forces to its border with Sudan in an effort to prevent smuggling into the Gaza Strip, due to intensive international pressure following Israel's offensive on the Hamas-ruled coastal territory earlier this year.

"The Egyptians are patrolling the border and inspecting it," a senior intelligence sources said. "They weren't doing that until now. They started doing it because of the increased international pressure to act against the smuggling. But so far, the results are only partial."

The Iranians are concerned over the memorandum of understanding signed between Israel and the United States to combat smuggling into Gaza, the source said. Eight NATO members also said they would join the anti-smuggling effort.

The Iranians see the recent interception of the arms ship Monchegorsk, which was en route to Syria, as a warning of the difficulties they are likely to face in delivering arms, the source added. That ship, which was carrying arms from Iran to the Syrian army, was stopped in Cyprus following American pressure and its cargo was confiscated.

The source said the Iranians, who established smuggling networks via the Persian Gulf, Aden and east Africa, with an emphasis on Sudan. In the past the Iranians have tried to smuggle arms via Turkey.

The routes planned to move weapons in planes, trucks and trains, and from Turkey to Syria and from Syria to Lebanon. A few of these shipments were caught by Turkish security services working against the smuggling.

News of Egypt's reinforcement efforts comes in the wake of foreign media reports saying that the Israel Air Force attacked a convoy of Iranian arms passing through Sudan en route to the Gaza Strip in Sudan in January.

Israeli officials declined to confirm or deny Israel's involvement in the air strike in Sudan. They also refused to comment on the various foreign media reports about the strike.

Arab and U.S. media reports said that Israel was behind the attacks, since the convoys were smuggling weapons destined for Gaza. Hamas, which rules Gaza, smuggles weapons into the Strip through tunnels along the Egyptian border.