Israel is allowing Egypt to deploy more armed forces in the Sinai desert, while at the same time telling its citizens to stay away.
The measures, announced Monday, reflect growing Israeli concern over potential attacks from Sinai. In August, militants infiltrated across the border and killed eight Israelis.
Israel withdrew from Sinai under its 1979 peace deal with Egypt. Under the accord, Sinai was mostly demilitarized, and only a few hundred Egyptian policemen were permitted there.
Since the fall of Egyptian President Hosni Mubarak in February, Israel has been allowing more Egyptian troops into Sinai to counter extremist Muslims, as well as Palestinian militants crossing from Gaza.
The Sinai desert is popular with Israeli vacationers, but in recent years Israel has urged citizens to avoid it because of past attacks.