Russia, a major ally of the Syrian government, said Thursday it was ready to conduct a 48-hour ceasefire next week to allow much-needed humanitarian aid into the divided city of Aleppo.
The measure will be considered a "pilot project" to determine the feasibility of future ceasefires in the area, Russian General Igor Konashenkov said.
Russia's military is ready to provide protection to United Nations convoys entering the war-torn northern city, Konashenkov told the Interfax news agency.
The Russian gesture came shortly after the UN envoy for Syria, Staffan de Mistura, adjourned a humanitarian task force meeting after just eight minutes, citing continued violence and a lack of progress on bringing aid into desperate parts of the war-ravaged country.
Russia has been carrying out an air campaign in Syria in support of President Bashar al-Assad since September 2015.
De Mistura welcomed Russia's statement, noting that the UN humanitarian team was set to mobilize. He said the UN's plan was to begin deliveries as soon as possible.
"The United Nations count on the Russian Federation to deliver their part regarding, in particular, the adherence of the Syrian armed forces to the pause, once it comes into effect," de Mistura's office said.
Fighting in Aleppo has intensified in recent weeks.
The UN humanitarian task force was set up in February to help coordinate aid deliveries to Syria where the warring parties have set up sieges and blocked supplies from reaching hard-hit areas.
Not a single aid convoy has reached besieged areas in Syria in over a month, de Mistura said.
In Washington, US State Department spokesman John Kirby stressed that discussions need to move beyond temporary ceasefires to a lasting humanitarian solution.
In Brussels, the European Union called for an "immediate halt" to fighting in Aleppo to allow medical evacuations, aid deliveries and essential infrastructure repairs.
Al-Assad's forces have been battling opposition rebels in south and south-western Aleppo for the last few weeks.
Aleppo, Syria's pre-war commercial hub, has been divided between Assad's forces in the west and rebels to the east since fighting erupted in mid-2012 for control of the city.
Last month, government forces captured the last remaining rebel supply route into the east, raising fears that some 250,000 to 300,000 civilians there would come under siege.
Earlier this month, rebel forces cut off the main government supply line to the west, prompting UN children's agency UNICEF to warn that about 2 million people on both sides of the city had no access to drinking water.
In recent weeks, Syria has seen multi-front fighting in different areas.
In an escalation of the country's five-year conflict, activists said that Syrian government warplanes bombed Kurdish positions for the first time Thursday in al-Hassakeh province in north-eastern Syria. The airstrikes come amid clashes that started this week between a US-backed Kurdish group and a militia loyal to al-Assad.
The government airstrikes targeted Kurdish forces in north-western and eastern parts of provincial capital al-Hassakeh, a monitoring group reported.
The Syrian Observatory for Human Rights said 25 civilians were killed and injured, including 10 children, amid an exodus to safer areas.
A Kurdish official said the regime's artillery shelling and air bombing were in response to Kurds' territorial breakthroughs against the Islamic State extremist militia in Syria.
"We will not stay silent over these bestial, flagrant attacks on our people," spokesman for the powerful Kurdish People's Protection Units (PYG), Redur Xelil, said in a Facebook statement.
The PYG and the Kurdish-led Democratic Force of Syria, both backed by the United States, have been instrumental against Islamic State fighters.
Most of al-Hassakeh is dominated by Kurdish forces affiliated with the People's Protection Units, which receives the backing of US airstrikes in its war against Islamic State forces.
The Kurds, who were up to 10 per cent of Syria's pre-war population of 22.4 million, live mainly in the north-east, as well as in small areas along the Turkish border.
Under al-Assad's Baath Party, the Kurds complained that they were denied many rights and that their culture was suppressed.
The Kurds have taken advantage of the 2011 uprising against al-Assad to further their push for autonomy.