At least some 250,000 people in an eastern Syrian city are under siege by Islamic State forces preventing the delivery of food and medical supplies, a monitoring group said Wednesday.
The price of food has rocketed in three government-held districts in the eastern city of Deir al-Zour since the jihadists sealed off the areas in early 2015, the Syrian Observatory for Human Rights said.
"Those people need urgent help by the international community as they are under siege and are unable to get their voice through to the world," Observatory director Rami Abdel Rahman said.
The warning came two days after the town of Madaya, besieged by government forces for six months, received its first supplies since October.
Reports of starvation in Madaya, a rebel-held mountain town near the Lebanese border where Doctors without Borders says almost 30 people have died for lack of food since early December, had caused a global outcry.
The United Nations says that, of the 4.5 million people in what it terms "hard-to-reach" areas of Syria, nearly 400,000 are living under siege.
"The sieges of all towns and villages across Syria need to be lifted, immediately and simultaneously," Robert Mardini, Middle East director for the International Committee of the Red Cross (ICRC), said on Wednesday.
"Whilst we wait for the sieges to be lifted, there needs to be unconditional, rapid and regular access given for humanitarian convoys to all these areas so that lives can be saved," he added.
In Geneva, senior officials from the United States and Russia met in Switzerland Wednesday to prepare for peace talks between Syria's warring sides. They are set for January 25.
Russia, along with Iran, is a key ally of Syrian President Bashar al-Assad, while the US, Turkey and Arab Gulf countries back opposition rebels.
US Assistant Secretary of State Anne Patterson met Russian Deputy Foreign Minister Gennady Gatilov and UN envoy on Syria Staffan deMistura in Geneva, a US diplomat confirmed.
The diplomats would also discuss the need for immediate and long-term humanitarian access to Syrians, Washington's Geneva mission said.
Representatives of all five permanent UN Security Council members, including the US and Russia, were scheduled to meet later on Wednesday in the Swiss city.
Al-Assad's fate is still a major sticking point among major world powers.
Russia and Iran refuse any agreement that would force al-Assad to step down, while the US and other countries backing the rebels want him out of power.
The Syrian government said Saturday that it is prepared to attend the Geneva talks, but demanded to first see a list of opposition representatives who would attend.
Kurdish-led forces who control much of northern Syria and have been the most effective group fighting Islamic State on the ground have also demanded to be represented at the talks.
In recent months, key world powers have stepped up diplomatic efforts to reach a political end to Syria's conflict, which is estimated to have claimed more than 250,000 lives.
The Islamic State extremist group has taken advantage of the conflict to seize large areas of eastern and northern Syria and the central desert.