In a statement posted to social media, the Saudi ministry urged "a comprehensive conference in Riyadh to bring together all southern factions to discuss just solutions to the southern cause". Riyadh said the Yemeni government had issued the invitation for talks.

Saudi Arabia and the United Arab Emirates have for years supported various factions within Yemen's government-run territories, intervening in the neighbouring country's long-running civil war.

One of those factions, the UAE-backed Southern Transitional Council (STC), is now pushing to declare independence and form a breakaway state, which would split the Arabian Peninsula's poorest state in two.

The STC, which has seized large swaths of territory in recent weeks, has announced plans for a two-year transitional process to establish a state in the south.

On Friday, airstrikes by a Saudi-led coalition left 20 dead, according to the separatists.

The Saudi-backed coalition was formed in 2015 in an attempt to dislodge the Houthi rebels from Yemen's north. But after a brutal, decade-long civil war, the Houthis remain in place while the Saudi and Emirati-backed factions attack each other in the south.