Israel must not ignore Egyptian violations of the Israel-Egypt peace accord, Foreign Minister Avigdor Lieberman told some 20 senior Israeli diplomats at a meeting on Tuesday.

Lieberman was referring to the deployment of Egyptian military tanks and aircraft into the Sinai Peninsula without Israeli permission, in contravention of the countries' 1979 peace treaty.

Egyptian authorities have been cracking down on militants in Sinai since an August 5 raid on an Egyptian border post that killed 16 border guards.

"We have to be insistent with the Egyptians and be strict about crossing every last 't,' because otherwise we will be on a slippery slope with regards to everything related to the peace agreement," Lieberman said.

Israel has already asked Egypt to remove the tanks from the areas close to the border, Maariv reported yesterday. The message was sent by Israeli security officials directly to Egypt, as well as via the U.S. government.

The spokesman for Egyptian President Mohammed Morsi told reporters on Monday that the president has not received any messages directly from Prime Minister Benjamin Netanyahu and that securing Sinai was an Egyptian national security requirement.