"Secretary Kerry expressed grave concern over the deteriorating situation in Syria, particularly for continued Russian and Syrian regime attacks on hospitals, the water supply network, and other civilian infrastructure in Aleppo", State Department spokesman John Kirby said in a written statement.
Moscow, Sep 28 Russian Federation has made public a package of agreements with the United States on the Syrian settlement, the country's Foreign Ministry said on Tuesday.
But he said ongoing communication between Kerry and Russian Foreign Minister Sergey Lavrov meant a truce brokered two weeks ago is "not dead".
He said Russian Federation considers the tone of the criticism unacceptable and "such rhetoric is capable of causing serious harm to the resolution process" in Syria.
Ali Shamkhani, head of Iran's National Security Council, was also reportedly quoted Tuesday as saying Aleppo's fate would be determined only "through a forceful confrontation".
Some 250,000 people in eastern Aleppo, a city in northern Syria, are still without safe drinking water after a pumping station was hit by attacks on September 22, the UN Children's Fund (UNICEF) reported on Tuesday.
A statement from the global charity, also known by its French acronym MSF, says both hospitals hit by airstrikes earlier Wednesday were severely damaged, causing the death of at least two patients and wounding two medics.
The ground component of the attack against several fronts of rebel-held areas in Aleppo launched by a coalition that includes Syria, Russia, and Iran, is "the biggest ground assault yet in a massive new military campaign that has destroyed a USA -backed ceasefire", notes Reuters.
Kerry said the burden was on Russian Federation to stop the assault and ensure humanitarian aid access, his spokesman John Kirby said.
Some 120 gunmen and their families are expected to leave al-Waer as part of an agreement to restore the government's authority over the neighborhood, Homs Governor Talal Barazi said.
Aleppo residents said the ferocious air attacks of previous nights had abated somewhat.
It attributes over 60 percent of the civilian fatalities in Syria to explosive weapons.
Addressing crowds in St Peter's Square in Rome on Wednesday, Pope Francis decried the bombing of Aleppo, saying those responsible for killing civilians would have to answer to God.
He called for utmost efforts to protect civilians in Syria's civil war, raging since 2011.
The Associated Press reported that despite government advances in the wake of reinvigorated Syrian and Russian air assaults, gains have been hard to consolidate.
Medical officials say airstrikes have severely damaged two hospitals in eastern rebel-held Aleppo, leading to the death of two seriously ill patients.
Wednesday's attacks saw the M10 and M2 hospitals hit before dawn, forcing both to shut temporarily, said Adham Sahloul of the Syrian American Medical Society, which supports both hospitals. Local medical workers said that two major hospitals were put out of service by the bombardment.
Speaking on condition of anonymity, a Syrian military official in Damascus told the AP news agency that operations in Aleppo will continue until "terrorists" in the eastern parts of the city are "wiped out". He said government forces had briefly taken over some positions there but were forced to withdraw.