The regime of Syrian President Bashar al-Assad recaptured the ancient city of Palmyra from the Islamic State extremist organization Sunday, in one of its most significant advances since Russia sent its air forces to al-Assad's aid in September.

State media and a monitoring group said that the 2,000-year-old city, a UNESCO-listed World Heritage Site, was in government hands after weeks of heavy fighting.

Troops and allied militiamen cleared Palmyra of all Islamic State fighters and "destroyed their last dens" there, state news agency SANA reported quoting an unnamed military source.

The report said that army engineers had cleared the city of mines and bombs laid by the retreating jihadists, who seized it in May and later set about systematically destroying its ancient monuments.

The recapture of the city, which is strategically located in Syria's central desert, was confirmed by the pro-opposition Syrian Observatory for Human Rights.

The Britain-based Observatory, quoting "multiple reliable sources," said that Islamic State fighters in the city had received orders from their leadership in the north-eastern city of al-Raqqa to withdraw.

The final overnight assault was accompanied by heavy air raids by Russian and Syrian forces as well as artillery shelling and rocket fire, the Observatory said.

The group said there were still sounds of gunfire in the east of the city as troops battled jihadists who had insisted on staying behind. SANA said the army was pursuing fleeing extremists eastwards into the desert.

The three weeks of battles culminating in the regime victory cost the lives of at least 400 Islamic State fighters and 180 government troops and allied militiamen, according to the Observatory.

The recapture of the city will be a major symbolic victory for al-Assad and for Russian President Vladimir Putin.

It is their greatest single gain against Islamic State since the launch of the Russian air campaign, which has also seen government forces isolate rebel-held areas of Syria's second city, Aleppo, from key supply routes north to the Turkish border.

The government defeats of last May, which saw Islamic State establish strategic dominance of the central desert, have now been largely reversed.

There was no immediate clarification as to the state of Palmyra's ruins, which date back to the first three centuries AD when the city was a powerful centre on trade routes through the Syrian desert.

Islamic State is known to have destroyed the main religious site, the Temple of Bel, the city's symbolic triumphal arch, and most of the tower tombs that stood on its outskirts.

Footage published by SANA of military operations on the outskirts of the city last week, however, appeared to show parts of the ruined city still standing.

Syria's head of antiquities, Maamoun Abdelkarim, told SANA on Saturday that the government intended to send a team of specialists to Palmyra as soon as it was recaptured to assess the extent of the destruction.

They would work under the supervision of UNESCO, given the city's World Heritage status, he added.

Latest news

Syrian opposition rules out future role for President al-Assad

The Syrian opposition said Friday it would not accept any role for President Bashar al-Assad in the future of the war-torn country, reacting to a recent US shift saying that removing al-Assad is no longer a priority for Washington.

Russian Army integrates breakaway forces of Georgian province

Parts of the small fighting forces of the Georgian breakaway province of South Ossetia have been placed under Russian military control, Russian Defence Minister Sergei Shoigu said on Friday.

Czech Republic's Pilsner Urquell beer is now Japanese

Japanese brewing company Asahi completed its takeover of the Czech brewery Pilsner Urquell on Friday, Asahi said in a statement.

Judge approves 25-million-dollar settlement of Trump University case

A US district judge on Friday approved a 25-million-dollar settlement of lawsuits and state fraud allegations against Trump University, the US president's now-defunct business venture.

Former Thai premier Thaksin to junta on reconciliation: 'Cut me out'

Former Thai prime minister Thaksin Shinawatra on Friday announced that he is not interested in the junta-led reconciliation process, three days after the junta handed him a half-a-billion-dollar tax bill for his past business deal.

Dalic: We welcome possible deal between Agrokor and banks

The government welcomes the possibility of an agreement being concluded between the Agrokor food company and creditor banks, and the bill on vitally important companies is not a fallback plan but the result of the government's care for the overall economic and financial stability of Croatia, Deputy Prime Minister and Minister of Economy Martina Dalic told a press conference in Zagreb on Friday.

Croatia, China sign action plan for cooperation in agriculture

The Croatian and Chinese ministries of agriculture on Friday signed an action plan for cooperation in the field of agriculture for the period 2017-2018, the Croatian ministry said in a statement.

ZSE indices up, Agrokor shares in focus of investor interest

The Zagreb Stock Exchange (ZSE) indices on Friday rose by more than 1.8%, with stocks of the Agrokor food and retail concern being in the focus of investor interest again.

Berlin police defend handling of Berlin market attacker

Berlin police defended themselves on Friday against accusations that they stopped surveillance on Berlin Christmas market attacker despite knowing in June 2016 he was dangerous.

Croatia, creditors tailor emergency measures to save tottering giant

Croatia's tottering retail and food giant Agrokor reached an agreement with its creditors, putting its debts standby and allowing it to continue working during emergency restructuring, the Croatian branch of Austria's Erste Bank said Friday.

Agrokor's creditors say standstill agreement to go into force today

A standstill agreement regarding the Agrokor concern's existing financial obligations to banks will take effect on Friday, additional capital will be injected into the concern in the coming days and the concern will be actively restructured, which includes a change of its management, it was said on Friday after a meeting between Agrokor's suppliers and creditor banks.

Palestinians, UN slam Israel's new settlement plan

Palestinians, Israeli activists and the UN lambasted the government of Israeli Prime Minister Benjamin Netanyahu on Friday, a day after it gave the go-ahead for the first new West Bank settlement in a quarter of a century.

South Sudan rebels release three abducted foreign oil workers

South Sudanese rebels have released three foreign engineers they abducted in early March in the oil-rich Upper Nile region, Foreign Affairs Ministry official Mawein Makol Arik said on Friday.

Turkish opposition: Imprisoned party chief has gone on hunger strike

The head of Turkey's pro-Kurdish opposition party has launched a hunger strike from prison.

European leagues threaten Champions League schedule clashes

The European Professional Football Leagues (EPFL) on Friday threatened schedule clashes on Champions League matchdays in an ongoing dispute with the governing body UEFA.

Danish court revokes citizenship of IS volunteer

A Danish appellate court on Friday stripped a man of his Danish citizenship for volunteering to fight for the extremist Islamic State in Syria.

Banks and Agrokor agree on key elements of standstill agreement

Member banks of the coordinating committee of financial creditors and representatives of the Agrokor food company have in principle agreed on key elements of a standstill agreement, which is expected to be signed later today, announcing changes in the company's management team, Erste Bank said in a statement on Friday afternoon.

Syrian man on trial in Sweden; mosque attack labelled terrorism

A Syrian man went on trial Friday in the southern Swedish city of Malmo, charged with terrorism and arson after an attack last year on a building used as an assembly hall by Shiite Muslims.