Beirut: One is a seasoned multi-lingual diplomat the other a relatively unknown rebel figure and student of Islam: the two men heading rival delegations at Syrian peace talks seem worlds apart.

The respective differences between government diplomat Bashar al-Jaafari and the opposition High Negotiations Committee's chief negotiator Mohammed Alloush in many ways mirror the vast gulf between the two sides at the talks.

The pair are in Geneva Switzerland for the latest UN-brokered talks after the last round collapsed in February.

Jaafari: Hawkish diplomat

Jaafari is a tall silver-haired diplomat who has been Syria's permanent envoy to the United Nations for nearly a decade.

For many he is the public face of a regime that has become an international pariah lambasted by rights groups and the West.

An unequivocal and sharp-tongued defender of the embattled government he is now tasked with making concessions at the peace talks.

"We are here to conduct indirect talks among Syrians without preconditions and without foreign intervention" Jaafari told reporters at the last round of talks.

Born in 1956 Jaafari hails from Damascus and belongs to the same Alawite religious minority as President Bashar al-Assad.

He holds degrees in French literature and translation and a doctorate in political science from the Sorbonne University in Paris. As well as his native Arabic he is also fluent in English and Persian.

Jaafari's first diplomatic posting was in Paris later moving to positions in New York and Indonesia.

Since Syria's conflict began in March 2011 with anti-government protests Jaafari has repeatedly deflected sharp criticism of Damascus at the UN.

He has doggedly rejected allegations of rights abuses by the regime including accusations of chemical weapons use in 2013 and well-documented starvation in the besieged town of Madaya.

When the leading diplomat railed against the UN's "baseless accusations" in 2014 a Qatari official described him as "delusional".

"His myopic and unquestioning analysis of the situation in Syria makes him difficult to engage with and ineffective as an interlocutor" said a UN Security Council diplomat.

"His argumentative performances in the Council do little to challenge the perception that he is less of a diplomat and more of a loudspeaker for Assad."

And Saudi journalist Mshari al-Zaydi has accused the Syrian ambassador of "complete moral recklessness".

Since March 2014 Jaafari has been restricted to a 40-kilometre (25 mile) travel radius around New York city where the UN headquarters are based.

Jaafari who is married to an Iranian wears his thin glasses low on his slender nose and a neatly trimmed goatee.

"People in Damascus have nicknamed him 'the lion of diplomacy' for his tough positions against his counterparts from the Gulf" a journalist with years of experience in Damascus told AFP.

"He's a ruthless negotiator and he understands very well what happens backstage at the UN."

Alloush: rebel in suit

Jaafari's opposite number Alloush the HNC's chief negotiator could hardly be more different.

Nearly 15 years younger he was born in Douma a besieged town east of Damascus subject to regular government bombardment that has killed hundreds.

A Sunni Muslim Alloush studied Islamic jurisprudence in Saudi Arabia making him relatively unknown even in his hometown.

One Douma resident told AFP that "no one here knows him".

Alloush is a leading political member of Jaish al-Islam (the Army of Islam) the most powerful rebel faction in the Eastern Ghouta region where Douma is located.

His prominent role within the HNC has boosted the body's legitimacy among rebels on the ground who have previously derided the opposition-in-exile as nothing more than suits in hotels.

Alloush is the cousin of slain Jaish al-Islam head Zahran Alloush killed in an air strike claimed by Syria's government in December.

An official biography provided by Jaish al-Islam to AFP says Mohammed has years of political -- but not fighting -- experience in the group.

Physically Alloush is also Jaafari's opposite sporting a beard on a rosy-cheeked face and a reserved demeanour.

Alloush is new to the corridors of the UN and his appointment as the HNC's chief negotiator has been controversial.

The HNC includes leading former politicians like Riad Hijab who defected from his post as prime minister in 2012 and Riad Naasan Agha a former culture minister.

Opposition members have criticised Jaish al-Islam for its alleged involvement in kidnapping prominent rights activists in Douma.

Some activists speculated that Alloush was chosen to provoke the regime and to "spite Russia because of the death of Zahran Alloush" a rebel source said.

"It will also very much embarrass the regime when they sit with him because for five years they've been saying that Jaish al-Islam are terrorists that shell Damascus -- so how can they sit with a terrorist?" he added.

AFP