The UN envoy for Yemen on Saturday launched a mission to discuss stalled Geneva peace talks as Saudi-led coalition warplanes pounded rebel positions across the war-ravaged country.

In the southern province of Abyan, a car bomb blast killed 12 rebels and wounded eight others, a local official said.

Coalition warplanes launched deadly air strikes against rebel positions in the southern city of Aden, a military official said, without giving figures.

But 48 hours of fighting there and rebel shelling with mortar rounds and Katyusha rockets killed nine people and wounded 132 others, a health official and a spokesman of anti-rebel forces in the port city said.

UN special envoy Ismail Ould Cheikh Ahmed, who flew in to Sanaa on Friday, said "all Yemeni parties must return to dialogue," quoted by the rebel-held sabanews.net.

A member of ousted president Ali Abdullah Saleh's General People's Congress told AFP the Mauritanian diplomat met Saturday with "senior leaders" of the party for talks on the Geneva conference.

But the source said the envoy did not meet with Saleh himself, who lashed out at Saudi Arabia in an interview with a Beirut-based television channel broadcast on Friday.

Saudi Arabia has been leading an air war since March 26 targeting Iran-backed Huthi Shiite rebels in Yemen and allied forces loyal to Saleh.

Clashes have also raged on the ground between the rebels and local militia fighting their advance, especially in southern Yemen.

The Geneva conference had been due to take place on May 28 but has been postponed, in a fresh blow to UN efforts to end a conflict estimated to have killed almost 2,000 people.

Speaking from Sanaa, Saleh said in the interview that he had rejected a Saudi offer of "millions of dollars" to drop his alliance with the Huthis.

Coalition warplanes struck a house of the ousted president in his home town of Sanhan, south of the capital, shortly after the interview was broadcast.

The former strongman no longer resides in his Sanhan home which has also been targeted in previous raids, and he is believed to be staying at a hotel in Sanaa.

Other raids on Friday night hit the rebel-held air force headquarters in Sanaa, arms depots in Sanhan, and Dailami air base, also in the capital, witnesses said.

Saleh was forced to resign in early 2012 after waging a bloody crackdown on a year of protests calling for an end to his three decades of iron-fisted rule.

His forces have been backing the Huthi rebels who seized Sanaa in September before fanning out across the country.

- Talks with Saudi -

In his interview, Saleh renewed calls for talks in Geneva between Yemeni parties as well as Yemen and Saudi Arabia -- which he accused of seeking to sow "sedition" in the war-torn country.

But "sooner or later we will hold talks with Saudi Arabia," said the former president who belongs to the Huthis' Zaidi offshoot of Shiite Islam.

Saleh said talks in Geneva, which he himself had first proposed, should focus on a "power transfer, choosing a new authority" and elections, as well as "condemning the Saudi aggression".

Yemen's government says it will only take part once rebels withdrew from at least part of the territory they have seized, in line with a UN Security Council resolution.

Riyadh, which has given refuge to Yemen's President Abedrabbo Mansour al-Hadi, hosted talks on May 17 that were boycotted by the Huthis but attended by figures from Saleh's party.

Other talks are reportedly being held in Oman where a Huthi delegation travelled on Thursday, two days after a visit by Iranian Foreign Minister Mohammed Javad Zarif.

Saleh said in his interview that the United States has also been holding talks in Oman.

Yemen's neighbour has good ties with both Tehran and Riyadh, and Muscat has often played the role of mediator.

It is the only member of the six-nation Gulf Cooperation Council not to have joined the Saudi-led air war.

Sabanews.net quoted a Huthi spokesman as saying that an "exchange of views and proposals with international and regional parties" were being aired in the sultanate.