Lebanese President Michel Aoun meets with Prime Minister Saad al-Hariri, and Lebanese Parliament Speaker Nabih Berri, February 6, 2018. Photo: Reuters / Mohamed Azakir.

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 the Lebanon-based, Iran-backed Shi’ite terrorist group Hezbollah.

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 UN 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 Defense 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 has an unresolved maritime border dispute with Israel over a triangular area of sea of around 860 square kilometers (330 square miles). The zone extends along the edge of three out of five energy blocks that Lebanon put to tender early last year.

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