RIYADH (AFP) - Saudi Arabia and Kuwait have urged their citizens to leave Lebanon immediately, days after Lebanese prime minister Saad Hariri announced his resignation while visiting Riyadh.

"Due to the situation in the Republic of Lebanon, the kingdom asks its nationals visiting or living in Lebanon to leave as soon as possible, and advises its citizens not to travel there," said a Saudi foreign ministry source, quoted by state news agency SPA.

Kuwait called on "all its citizens to leave Lebanon immediately" and avoid going there as a precautionary measure, state agency KUNA quoted a source at the foreign ministry as saying.

On Nov 4, Hariri announced in a televised speech from Saudi Arabia that he was stepping down, citing Iran's "grip" on Lebanon and threats to his life.

The shock announcement raised fears that Lebanon - split into rival camps led by Hariri and the Iranian-backed movement Hezbollah - could once again descend into violence.

Hariri, who also holds Saudi nationality and whose wife and children live in the kingdom, has since met Saudi King Salman and travelled to the United Arab Emirates, according to official media in the Gulf states.

Lebanese President Michel Aoun has said he will await Hariri's return before taking any decision, while Hezbollah chief Hassan Nasrallah said Hariri's resignation had been "imposed" by Saudi Arabia.

The resignation coincided with the announcement in Saudi Arabia of an anti-corruption purge in which dozens of princes, ministers and businessmen have been rounded up.

Bahrain, a close ally of Saudi Arabia, advised its citizens against travel to Lebanon a day after Hariri's announcement.