GENEVA (AP) — The Latest on developments in Syria and the Geneva talks (all times local):
A senior member of the Syrian opposition delegation in Geneva has singled out Iran as the biggest obstacle to settling the conflict in Syria.
Nasr al-Hariri said in comments to reporters that violations to a cease-fire brokered by Russia and Turkey have continued across the country.
He said the guarantor countries, "specifically Russia, failed to control the regime and the militias that fight with the regime, they failed to control Iran."
Hariri spoke moments after the United Nations envoy to Syria, Staffan De Mistura, welcomed the Syrian government and opposition representatives to talks.
He said Iran was playing a negative role not only in Syria but also the broader region, calling it the biggest obstacle to regional understanding.
He urged Washington to re-engage in the region and put an end to the interventions of Iran, which has "spread tens of thousands of sectarian fighters."
He said, "There needs to be a regional, international effort to put a stop to Iranian interventions in the region. This is what is expected from the United States."
The United Nations envoy for Syria is officially welcoming a government delegation and envoys for the opposition at a ceremony at the U.N. office in Geneva, saying they all face a historic moment for Syrian people who "desperately want a resolution."
Flanked by the two delegations at a vast assembly hall at the U.N.'s headquarters in Europe, Staffan de Mistura spoke to diplomats from regional and world powers including the United States and Russia, saying "we are launching a window of opportunity" to see if a political "road forward" can be found.
"The Syrian people all want an end to this conflict and you all know it," he said, addressing the two sides. "They are waiting for a relief of their own suffering, and the dream of a new road out of this nightmare to a real and normal future in dignity."
He said a recent, fragile cease-fire "will face many challenges" and said it needs to be strengthened.
The talks are the first under U.N. auspices in Geneva in 10 months, and marks the first time under de Mistura's nearly 3-year tenure that the two sides have sat face-to-face under U.N. mediation.
Russian President Vladimir Putin is voicing hope for the success of a political settlement in Syria, saying it will help defeat the "terrorist malaise."
Putin said Thursday at a meeting with Russian seamen that Moscow's goal in Syria is to help stabilize the legitimate government and fight international terrorism.
Russia has conducted an air campaign in Syria since September 2015, helping turn the tide of war in Syrian President Bashar Assad's favor.
Putin said the Russian military action had helped create conditions for talks between the government and the opposition in Kazakhstan's capital, Astana. He voiced hope that the process launched in Astana will be developed at the Syria peace talks in Geneva, which opened Thursday.
President Vladimir Putin says Russia is protecting its security with a military campaign in Syria.
Putin said Thursday that about 4,000 people from Russia and another 5,000 from other ex-Soviet nations have joined militants in Syria. He added that they pose a major threat to Russia.
Russia has waged an air campaign in Syria since September 2015, shoring up President Bashar Assad and helping his troops gain some key ground.
Speaking at a meeting with Russian seamen who took part in a Russian aircraft carrier group's mission near Syria's shores, Putin said it was successful and helped gain valuable experience.
The Admiral Kuznetsov carrier and escort ships have returned to their home base earlier this month. The mission marked the first use of Russian carried-based aircraft in combat.
The Turkish defense minister has confirmed that Turkish troops and allied Syrian fighters have entered the center of the Islamic State-held town of al-Bab.
Fikri Isik told reporters on Thursday that the forces were continuing sweeping the area for remaining insurgents, adding that the town would soon be totally cleared of the extremists.
"Al-Bab is almost totally taken under control and (the forces) have entered the center," Isik said. "We will be able to say that al-Bab is fully cleared of Daesh once the sweeping activity is concluded."
He was using the Arabic name for the IS group.
The U.N. envoy for Syria has held a moment of silence with a group of Syrian women bearing a message that expressed hope that the fate of detainees, abducted people and the missing will be discussed in new intra-Syrian peace talks.
Staffan de Mistura told reporters "you can be sure that we will be constantly raising detainees, abducted and missing people" during talks between government and opposition envoys. He said he hoped to start later Thursday the "bilateral" talks between the two sides.
De Mistura said he was waiting for delegations to arrive and was planning "some type of welcoming opportunity" for them, without elaborating.
He said the women were "Syrian mothers, Syrian wives, Syrian daughters, who are representative symbolically all those Syrian men, women, sometimes children who are being arrested, abducted, or are missing."
"There are thousands and thousands of mothers, wives, daughter who are hoping that at least this aspect will be one of the benefits of any negotiation," he added.
Turkey's state-run news agency says Turkish troops and allied Syrian fighters have seized the center of the town of al-Bab from the Islamic State group.
Anadolu Agency, quoting a Syrian opposition force commander Ahmed al Shahabi, said Thursday the troops were clearing mines and other explosives left behind by the IS militants.
Turkey sent troops across the border into northern Syrian in August to help Syrian opposition forces battle IS and halt the advances of U.S.-backed Syrian Kurdish fighters.
The troops had become bogged down in a grueling battle over al-Bab, one of the few remaining IS strongholds in northern Syria.
Syrian peace talks under the auspices of the United Nations have resumed in Geneva, 10 months after they fell apart over escalating bloodshed in the war-torn country.
U.N. Syria envoy Staffan de Mistura is convening his first morning meeting with the delegation of the Syrian government, headed by Bashar al-Ja'aafari, on Thursday.
He is then expected to meet with Nasr Hariri, a senior member with the largest opposition group, the Syrian National Coalition.
Opposition delegates have been arriving in Geneva since Wednesday and some held late night meetings in preparation for the talks.
This is the fourth round of negotiations since early last year.
The talks are taking place amid a hard-won, fragile truce brokered by Turkey and Russia, which have backed opposite sides in the six-year civil war.