The United States has accused Russia of holding the United Nations Security Council "hostage" over the Syria chemical weapons crisis.
US Ambassador to the UN, Samantha Power, said she can see no way to seek Security Council approval for action against President Bashar al-Assad because Russia is trying to protect the government of President Bashar al-Assad.
She said Russia's response has created complete deadlock in the Security Council.
Ms Power said a draft resolution Britain submitted to the five permanent council members last week calling for a response to the use of chemical weapons in Damacus on 21 August, is effectively dead.
President Barack Obama is seeking approval from the US Congress for a military strike against Syria.
Meanwhile at a G20 meeting in St Petersburg, President Vladimir Putin wants to talk Mr Obama out of military action. So far he has found agreement from China, the European Union and Pope Francis.
United Nations secretary general Ban Ki Moon is pressing for an international peace conference on the crisis.