Maduro praised the deal on Twitter, saying it "opens the way for a new chapter for Venezuela, to keep advancing towards the peace and well-being that all Venezuelans yearn for."
Crisis-hit Venezuela is no stranger to seasonal storms, but this was the worst so far this year following historic rain levels that caused dozens of deaths in recent months.
A landslide in central Venezuela left at least 22 people dead and more than 50 missing after heavy rains caused a river to overflow.
The freeing of Americans could create political space for the Biden administration to ease crippling oil sanctions on Venezuela if Maduro shows progress in talks with his opponents.
"The president made a tough decision, a painful decision, to offer something the Venezuelans have actively sought" in the months-long swap negotiations, the official added.
Alongside the likes of Russia, China, Cuba and Turkey, Iran is one of Venezuela's main allies. And like Venezuela, it is subject to tough US sanctions.
It will also evaluate the Russian offer to sell crude oil at discounted prices after considering aspects such as insurance and freight required to move the fuel from the non-traditional supplier.
The US delegation that traveled to Caracas at the weekend discussed energy supplies with Maduro, as Washington looks for ways to replace Russian oil imports in the backdrop of Russia's war on Ukraine
Protesters said they were heeding the opposition's call for another mass demonstration despite the heavy-handed response by security forces over the last week to quell anti-government protests.
Expressed in the previous "strong bolivar" currency in effect until Monday, it amounts to a hike from 248,210 to 6,000,000 to the dollar.
John Boquett, a firefighter captain in Caracas, said there were no initial reports of injuries or major damage in the capital.
Opposition critics slammed the plan as inadequate in the face of inflation that topped 82,000 percent in July and called for a one-day halt of commercial activities.
Priests have had to adapt and start accepting donations by card payments rather than the traditional passing around of a wicker basket for churchgoers to drop in some coins, or even notes.
Oil-rich Venezuela has been in an economic freefall since a drop in oil prices in 2014 left a gaping hole in the country's finances.
Maduro, who has systematically sidelined the opposition as he tightens his grip over his troubled nation, accuses the opposition and Colombia of being behind Saturday's drone "attack."
Last year, the European Union hit the Venezuelan vice-president and 10 other officials with sanctions over rights abuses and irregularities in the re-election of Maduro.
Venezuela arrests six terrorists over attack on President Nicolas Maduro as opposition fears reprisals
Venezuela's socialist government alleged Sunday that the detained suspects conspired with others in Miami and the capital of neighbouring Colombia, though they offered no specific evidence.
Maduro said he had escaped an "assassination" attempt using an explosive-laden drone during a Caracas military parade, which the government said injured seven soldiers.
Maduro accused neighboring Colombia and unidentified "financiers" in the United States of being behind the blast, while some of his officials blamed Venezuela's opposition.
The head of the assembly, Diosdado Cabello, tweeted that Maduro and the assembled military chiefs had survived a "terrorist attack" he blamed on the opposition.