Foreign Minister Julie Bishop has called on the United States and Russia to consider an arms embargo in Syria to force the Assad regime and its opponents to the negotiating table.
Having witnessed two recent meetings between US Secretary of State John Kerry and his Russian counterpart, Sergei Lavrov, Ms Bishop says it's clear all trust has broken down.
"Neither side trusts the other side and while the Assad regime, backed by Russia and Iran, believes that it can win militarily over the opposition groups, backed by the US and the Gulf countries, the killing and the war will continue," she told ABC TV on Sunday.
It is vital a political and diplomatic solution is found for the conflict.
"One option would be for both sides to withdraw military support from the regime, from the opposition groups and force them to the negotiating table," Ms Bishop said.
At the very least, she says talks between the two sides and their proxies must agree to reinstate a ceasefire so aid can reach citizens and towns devastated by bombing.
"It seems that Russia has given up any pretence of a ceasefire at this point and the violence and the atrocities going on in Aleppo are unprecedented," he said.
"They have to continue to talk because the indiscriminate bombing is killing thousands of civilians."
If the US were to abandon its proxy role and begin bombing the Assad forces directly that would lead to "all-out war".
