Lebanon on Monday received the first French weapons in a $3 billion Saudi-funded program intended to bolster its army to take on jihadist threats, particularly along its border with Syria.

French Defense Minister Jean-Yves Le Drian accompanied the first tranche of weapons, including anti-tank guided missiles, which were handed over at an air force base in Beirut.

"France and Lebanon have a fraternal relationship that has been marked over the past three years by a sharp deterioration in the security situation in the Levant, which has become an existential threat to the region," Le Drian said.

"Lebanon is under unprecedented pressure (from jihadist groups)... and this makes border control vital for its security," he added.

"In this critical context, it is therefore essential that Lebanon's friends and allies mobilize to contribute to its security and stability."

Over the next four years, France is expected to deliver to Lebanon 250 combat and transport vehicles, seven Cougar helicopters, three small warships and a range of surveillance and communications equipment.

The entire $3 billion (2.8 billion euro) cost of the program is being borne by Saudi Arabia, which has close ties with some of Lebanon's leading political figures.

The contract also promises seven years of training for the 70,000-strong Lebanese army and 10 years of equipment maintenance.

At the ceremony on Monday, Lebanon's Defense Minister Samir Mokbel welcomed the delivery, saying the country's fight against extremism was a common battle.

"A victory for Lebanon against terrorism is a victory for all countries, near and far, who are threatened by terrorism," he said.

He thanked Saudi Arabia for financing the weapons delivery and France for "its deep understanding of all the threats that Lebanon faces, whether militarily at the border, or internally with the influx of refugees that threatens general stability."

Saudi ambassador to Lebanon Ali Awad Asiri said the kingdom's financing came as "Lebanon faces more challenges than ever."

"The kingdom's gift will support the Lebanese army and legitimacy in Lebanon," he said.

"It is support for a legitimate army that ensures stability at a time when Lebanon faces security challenges."

Despite being on the frontline against jihadist groups along the border, Lebanon's army remains significantly less well armed than the country's powerful Hezbollah movement, which is backed by Riyadh's regional rival Tehran.

Saudi Arabia has also donated another $1 billion to Lebanon through its key ally, former prime minister Saad Hariri, that is intended to support the army and police.

In recent months, Lebanon's army has waged multiple battles against jihadists from the Islamic State group and al-Qaida Al-Nusra Front.

Last August, extremist fighters from the two groups briefly overran the Lebanese border town of Arsal, seizing several dozen Lebanese soldiers and police.

The groups have since executed four of the hostages, with a fifth dying of wounds he sustained during the fighting. They are still holding 25 Lebanese.

The conflict in Syria has exacerbated sectarian tensions in Lebanon, and the influx of more than one million refugees has tested its limited resources.

Former colonial power France is actually a latecomer to the conflict, with almost all Lebanon's international support coming from the United States and Britain in recent years.

Washington has provided around three-quarters of Lebanon's foreign military aid over the past decade — some $700 million — as well as special forces teams to train its elite units, according to IHS Jane's, a London-based think tank.

Britain has provided training facilities as well as watch towers and forward operating bases along the border with Syria.