The United States has shared with its UN Security Council allies a draft resolution calling for international aid to be delivered in Venezuela and for a presidential vote to take place.
While no date has yet been set for a vote on the American draft, and negotiations are ongoing, Russia is likely to use its veto power to block it as part of its support of Nicolas Maduro's regime, diplomats said.
The text, a copy of which was obtained by AFP on Saturday, expresses "full support for the National Assembly as the only democratically elected institution in Venezuela."
The legislative body's chairman, Juan Guaido, has declared himself interim president of Venezuela, challenging Maduro's rule.
The draft resolution stresses "deep concern with the violence and excessive use of force by Venezuelan security forces against unarmed, peaceful protesters."
It also "calls for the immediate start of a political process leading to free, fair and credible presidential elections, with international electoral observation, in line with Venezuela's constitution."
The text also requests that UN Secretary General Antonio Guterres "utilize his good offices" to obtain such elections.
It also "stresses the need to prevent further deterioration of the humanitarian situation in Venezuela and to facilitate access and delivery of assistance to all in need in the entirety of the territory of Venezuela."
On Friday, Moscow proposed an alternative text to the American one, diplomats said.
Humanitarian aid sent by the United States recently arrived in the Colombian city of Cucuta at the border with Venezuela, but Maduro has refused to let in the shipments.
Guaido said Friday he was ready to take any necessary measures, including authorizing a US military intervention, to force Maduro from power and alleviate the humanitarian crisis.