Lebanon’s top three leaders accused Israel on Tuesday of threatening the stability of the border region between them, amid rising tension over territorial and maritime boundaries.

President Michel Aoun, Prime Minister Saad al-Hariri, and Parliament Speaker Nabih Berri agreed to act to stop Israel from building a wall on Lebanese land at the border, and infringing on an energy block in disputed waters.

Arguments over the wall and Lebanon’s plans to explore for offshore oil and gas have elevated tensions between Israel and Lebanon.

Calm has largely prevailed along the frontier since 2006, when Israel fought a war with Lebanon’s heavily-armed Shi‘ite Hezbollah movement.

The month-long conflict killed about 1,200 people in Lebanon, mostly civilians, and 160 Israelis, most of them troops. There has been no major confrontation between Israel and Iran-backed Hezbollah since.

Israel has said the border wall is being built on its territory. The Lebanese government says it passes through land that belongs to Lebanon but lies on the Israeli side of the Blue Line, where the U.N. demarcated Israel’s withdrawal from southern Lebanon in 2000.

The three Lebanese leaders met to study recent “Israeli threats, and saw in them … a direct threat to the stability” of the border region, the president’s office said in a statement.

They agreed to act “at various regional and international levels to prevent Israel from building the cement wall…and from the possibility of infringing on Lebanon’s oil and gas wealth and its (territorial) waters.”

Aoun, Berri, and Hariri will present a series of measures to Lebanon’s Higher Defense Council and security officials at a meeting on Wednesday, it said.

Israeli Defence Minister Avigdor Lieberman called Lebanon’s first offshore oil and gas exploration tender “very provocative” and urged international firms not to participate last week.

Lebanon in December approved a bid by a consortium of France’s Total, Italy’s Eni and Russia’s Novatek for two blocks.

REUTERS