The UN Security Council on Monday renewed the cross-border aid mechanism to Syria for another six months, a length of time that several member nations consider too short.
The 15-member Council voted unanimously to extend life-saving assistance to millions of people living in northern Syria, until 10 July.
The aid delivery mechanism across Turkey's border into rebel-held Syria at the Bab al-Hawa crossing is the only way UN assistance can reach civilians without traversing areas controlled by Syrian government forces.
The mechanism is in place since 2014 and was due to expire on Tuesday. It was last renewed in July, also for only six months at the insistence of Syria's ally Russia.
The Bab al-Hawa crossing supplies more than 80 percent of the needs of people living in rebel-controlled areas.
Moscow has, for years, pressured international organizations to pass exclusively through regions under the control of Damascus to distribute aid throughout the country, going as far as vetoing cross-border extensions that exceeded six months.
The United States, France and others said they had wanted the mechanism extended for one year.
"The debate we need to have is how to strengthen the mechanism to reach more people with more assistance," said US Ambassador Linda Thomas-Greenfield, describing the resolution as "the bare minimum."
Moscow's UN envoy, Vassily Nebenzia, said Russia's support of the six-month extension "should not be viewed as a change in our principled position" on the mechanism, calling for "respect for Syria's territorial integrity."
In 2014, international aid could flow to Syria through four border crossings, but after years of pressure from China and Russia, only the Bab al-Hawa route has remained operational.
Syrian Kurds
Meanwhile, the Kurdish-led Syrian Democratic Forces (SDF) said last Friday they had arrested more than 100 "terrorists" in an eight-day operation against Islamic State group militants active in the north east of Syria.
Kurdish-led forces launched the sweep dubbed Operation Al-Jazeera Thunderbolt last week, after thwarting an IS attempt to free fellow militants from prison in Raqa, the jihadist group's former Syrian stronghold.
The Syrian Kurds have been seeking to underline their value as a partner to the West in its campaign against IS as NATO ally Turkey keeps up its threats to launch a new cross-border assault against territory under Kurdish control.
"During the sweep and raid operations, our forces arrested 154 wanted terrorists and criminals," the SDF said in a statement.
Those arrested included 102 suspected IS cell members and 27 others suspected of providing logistical aid, the statement added.
SDF fighters swept 55 villages and farms in the east as well as "large areas of the Syrian-Iraqi border".
The SDF said the operation was carried out alongside troops of the US-led coalition, although there was no immediate confirmation from the international force.
It prevented attacks on the main Kurdish cities of Hasakeh and Qamishli during the Christmas and New Year holidays, the statement said.
Last week's foiled prison break in Raqa was the most significant IS operation in Syria since a successful break from Ghwayran prison in Hasakeh last January.
Dozens of jailed militants escaped and the ensuing clashes killed hundreds.
Three of the suspects detained in the past week's sweep were implicated in providing bombs and other equipment for the Ghwayran attack, the SDF said.
Although IS is a pale reflection of the organisation that seized vasts swathes of Syria and neighbouring Iraq and declared a "caliphate" in 2014, it still boasts a network of sleeper cells on both sides of the border that remains capable of carrying out deadly assaults.
Attacks blamed on IS militants in eastern Syria killed 12 oil workers and a Kurdish fighter last week.
(With agencies)
