Egypt has discreetly boosted the number of troops deployed along the border with the Hamas-controlled Gaza Strip, beyond those set in a 30-year-old peace accord with Israel, Israeli officials said Tuesday.

The officials, speaking on condition of anonymity, said reinforcements started arriving after Hamas Islamists in Gaza blasted open the Egyptian border at Rafah on Jan. 23 in defiance of an Israeli-led blockade of the coastal territory.

"We don't see the current levels as a threat at the moment," a senior Israeli official said of the increased Egyptian troop presence. "We have not objected to it. But no long-term arrangement has been made."

Israeli officials estimated that up to 1,500 Egyptian border guards were now along the Gaza border, double the formally agreed-upon level.

An Israeli defense official said Israel was aware of the reinforcements, calling it part of a "tacit agreement" to reduce the risk of another attack on the border.

Last month's border breach allowed hundreds of thousands of Palestinians to cross into Egypt's Sinai desert. Egypt closed the border 12 days later, but an agreement has yet to be reached on how the border will be managed in future.

On Tuesday, Military Intelligence Chief Amos Yadlin told the Knesset Foreign Affairs and Defense Committee that terror activists trained in Syria and Iran had infiltrated the Gaza Strip from Egypt through the breached border.

The Egyptian Foreign Ministry could not be immediately reached for comment.

But Egyptian security sources said only civilian police were being allowed into the border area to help with security as needed and that this was within the scope of the border agreement with Israel.

Egypt has sought formal Israeli approval to double the number of troops at the border to 1,500.

Israel's Foreign Ministry had suggested giving the nod to the Egyptian request but the Defense Ministry objected, arguing that it would require reopening the 1979 peace accord.

Under the peace agreement, the number of troops that can be deployed between the Egyptian Sinai and Gaza was limited to 750.

Yuval Steinitz, a senior member of the opposition Likud party and a former chairman of the Knesset Foreign Affairs and Defense Committee, called any increased Egyptian troop deployments "very serious".

Steinitz said he was aware of Egypt sending three battalions - roughly 600 to 900 soldiers - of reinforcements.

"This compromises the demilitarization of the Sinai," he said. "Today it's a few battalions. Tomorrow there might be far more."