Censor.NET reports citing Daily Mail.
The allies pressed Moscow to allow unfettered humanitarian assistance, halt the Syrian regime's "indiscriminate" bombing of its own people and create the conditions necessary to resume political transition talks led by the United Nations.
"The burden is on Russia to prove it is willing and able to take extraordinary steps to salvage diplomatic efforts," the joint statement reads.
"The outrageous bombing of a humanitarian convoy, the Syrian regime's public denunciation of the CoH, continuing reports that the regime is using chemical weapons, and the unacceptable ongoing regime offensive on eastern Aleppo, supported by Russia, blatantly contradicts Russia's claim that it supports a diplomatic resolution," the diplomats stressed.
The allies called on Russia to "restore the credibility of our efforts, including by halting the indiscriminate bombing by the Syrian regime of its own people, which has continually and egregiously undermined efforts to end this war."
They demanded "immediate, expanded" humanitarian access to all parts of Syria, deploring "delays and obstruction caused primarily by the Syrian regime of humanitarian deliveries to Syrians in desperate need."
They also reaffirmed their commitment to destroying the Islamic State group and urged Russia to focus on the jihadists as well.
"Patience with Russia's continued inability or unwillingness to adhere to its commitments is not unlimited," the document reads.
The group pressed the UN Security Council to "take urgent further steps to address the brutality of this conflict, and particularly the assault on Aleppo."
Related materials: Russian killer pilots in Syria