A UN investigation committee on Syria has been able to access the country for the first time since the start of the Syrian revolution in 2011, after ousted Syrian President Bashar al-Assad had previously refused to enter.

The UN investigator tasked with looking into human rights violations during the uprising in Syria, Hanny Megally, said that Assad never granted investigators permission to enter Syria, but the new authorities did so "immediately."

Megali added in a statement to Agence France-Presse that he hopes the committee will be able to establish a good relationship with the current authorities.

The commission has been investigating war crimes and other violations of international human rights law since the start of protests and the outbreak of war in Syria in 2011, and has so far carried out its work remotely, compiling lists of 4,000 people suspected of committing serious crimes.

Megali said he had visited detention centres and mass grave sites in and around Damascus, and had held talks at the ministries of justice and foreign affairs, explaining that the commission wanted to be able to visit the sites it had documented to "reconfirm the information" it had collected and fill in the gaps.

Don't repeat the past

The commission, which has investigated all parties involved in the Syrian conflict, including former opposition figures now in power, also wants to work with current authorities "to ensure that the past does not repeat itself."

"No party to the conflict in Syria can say: 'We have respected human rights or international humanitarian law,'" Megali said, adding, "But we are now in a new phase, and it would be good to be able to say that lessons have been learned."

On December 8, the armed Syrian opposition factions took control of the capital Damascus and other cities before that, thus ending 61 years of Baath Party rule and 53 years of Assad family control.

The next day, the leader of the new Syrian administration, Ahmed al-Sharaa, announced that Mohammed al-Bashir (the head of the government that had been running Idlib for years) had been tasked with forming a new government to manage a transitional phase.