Leaders of five UN agencies have appealed to the international community to stop the "cruelty and carnage" in Syria, warning they may soon be forced to suspend humanitarian aid to the war-torn country.
The UN leaders said on Monday that their "capacity to do more was diminishing, due to security and other practical limitations within Syria as well as funding constraints".
"We are precariously close, perhaps within weeks, to suspending some humanitarian support," the UN leaders said.
"We, leaders of UN agencies charged with dealing with the human costs of this tragedy, appeal to political leaders involved to meet their responsibility to the people of Syria and to the future of the region.
"The international community needs to find a political solution to this conflict before the human carnage grows and grows from a crisis to what is already becoming a catastrophe."
Al Jazeera's Diplomatic Editor James Bays, reporting from the UN, said the document was unusual not only because it was rare for the heads of the major UN agencies to write a joint letter, but also because of the tone they used.
The statement sought to hold the spotlight on the conflict in Syria in which more than 70,000 people have been killed and more than five million people have been driven from their homes, including one million refugees.
"After all this, there still seems an insufficient sense of urgency among the governments and parties that could put a stop to the cruelty and carnage in Syria," they stressed.
The statement was signed by UN Emergency Relief Coordinator Valerie Amos, Executive Director of the World Food Programme Ertharin Cousin, UN High Commissioner for Refugees Antonio Guterres, Executive Director of the UN Children's Fund Anthony Lake and Director-General of the World Health Organization Margaret Chan.
The rare appeal from the UN agencies came on a day President Bashar al-Assad declared a general amnesty for crimes committed in the war-torn country prior to Tuesday, according to the official SANA news agency.
The SANA news agency said that under the latest amnesty, which was to take effect immediately, "the death penalty will be replaced with a life sentence of hard labour".
The amnesty would give lighter sentences to people convicted of joining the rebellion, but it would not apply to those found guilty of smuggling weapons or drug-related crimes, SANA added, quoting the text of the decree.
"Syrians who joined a terrorist organisation will only have to serve a quarter of their sentences," said the decree.
Meanwhile, Syrian activists have said that there has been an explosion in the al-Baramka neighbourhood of central Damascus.
Air strikes against rebel forces in other parts of the capital have also been reported, while regime warplanes attacked the Qaboun neighbourhood of the capital just days after 20 people, mainly children, were killed in another air strike.