Guaido and the opposition-dominated National Assembly he heads have branded Maduro a "usurper" over his re-election last May in a poll boycotted by his opponents protesting the detention, exile and barring of many of their leaders.
"I won legitimately", he said of last year's election. U.S. National Security Adviser John Bolton has warned that any harm to Guaido or the National Assembly he presides over would be considered a "grave assault" and be met with a "significant response", without specifying.
A former union leader, bus driver and foreign minister, Maduro has overseen a shrinking economy and the migration of 3 million Venezuelans fleeing shortages and hyperinflation.
Sabatini said that, with the new sanctions, Venezuela will not be able to immediately export to other countries because of the technicalities of processing its heavy crude.
"There are different models of national security advisors, but most have played the role of policy umpire - convening other principals to provide the President with the wisest consensus advice", said Ned Price, who served as a National Security Council spokesman for President Barack Obama.
On Monday, the US imposed sanctions on Venezuela's state-owned oil company, Petroleos de Venezuela SA, that could potentially deprive the Maduro government of $11 billion in export revenues over the next year.
Maduro however, still has the backing of the army although Mr Guaido has offered amnesty to any military personnel who want to defect.
U.S. military invention is seen in Washington as highly unlikely, but President Donald Trump has repeatedly said "all options are on the table".
President Nicolas Maduro said that he was open to talks with the United States of America.
Sources told Reuters that private military contractors who do secret missions for Moscow were in Venezuela last week.
Venezuela's opposition plans protests Wednesday to urge the military, the lynchpin of Maduro's beleaguered regime, to dump him in favor of self-declared interim leader Juan Guaido.
Since Maduro announced to sever diplomatic ties with the United States, the conflict between the two countries has been fermenting.
Guaido called for more protests on Wednesday and a mass march at the weekend, to keep up pressure on Maduro in the streets.
The statement said they were "ready to work with those members of the worldwide community. who want to employ diplomacy" to find a way out of the Venezuela crisis. More than 40 people have died so far in and around the protests that began a week ago, the United Nations human rights office said.
"A campaign has been prepared to justify a coup d'etat in Venezuela, which has been prepared, financed and supported actively by the Donald Trump administration", said Maduro on social media Tuesday.
"The United States is a great country and it is much bigger than Donald Trump", he said.
With the increased penalties on Venezuela, the Trump administration aims to force Maduro to cede the presidency as he loses support from the armed forces, whose continued loyalty to him has been crucial to his retaining power.
So far, the military high command has remained loyal to Maduro.