"All the evidence we have points to that conclusion," one of the officials said.
The White House position is that Russia is responsible, whether it was Russian planes -- or the Syrian regime's -- that carried out Monday night's attack.
The aid convoy was hit in the area of Urum al-Kubra, west of Aleppo, prompting the United Nations to halt its aid operations in Syria.
It is not clear who was responsible for the strike, which the International Committee of the Red Cross said killed about 20 people as well as the director of the Red Crescent's Urum al-Kubra branch, Omar Barakat.
"All of our information indicates clearly that this was an airstrike. That means there only could have been two entities responsible," deputy national security adviser Ben Rhodes said Tuesday night, referring to Russia and Syria. He didn't specify which country's planes carried out the strike.
"We hold the Russian government responsible for airstrikes in this airspace given their commitment under the cessation of hostilities was to ground air operations where humanitarian assistance was flowing," Rhodes said, referring to the terms of a recent ceasefire brokered between the United States and Russia.
Denials from Russia, Syria
Russia denies it was responsible and says that terrorists carried out the attack.
Defense Ministry spokesman Igor Konashenkov said Tuesday that analysis of video footage from drones of the strike show that militants were following the convoy, according to the Russian state news site Tass.
"It is clearly seen in the video that a terrorists' pickup truck with a towed large-caliber mortar is moving along with the convoy," he said.
Syria has also strongly its forces were behind the attack.
UN Secretary General Ban Ki-moon
called the attack "sickening, savage and apparently deliberate."
"Just when we think it cannot get any worse, the power of depravity sinks lower," Ban told world leaders convening Tuesday at the UN General Assembly annual meeting.
Eighteen of the convoy's 31 trucks were hit, the United Nations said. The convoy was due to deliver food and medical aid for some 78,000 people in eastern Aleppo, where an estimated 250,000 civilians are facing severe shortages as a result of a government siege.
Rebels, locked in a vicious civil war with the Syrian government, reportedly hold the area where the convoy was struck. Russia has been helping Syrian President Bashar al-Assad in the fight, though it has said its efforts are focused on attacking terror groups such as ISIS that have flourished during the conflict.
The US military has been reviewing classified radar, signals and aerial surveillance intelligence.
Based on that intelligence and reports from the ground, it has concluded that only Russian warplanes were in a position to attack this location at the time, the official said.
For now, no intelligence indicates Syrian aircraft or helicopters were in the area, though that type of information could come to light later, the official said.
The official added that reports from the ground appear accurate about at least two waves of airstrikes -- a common Russian military practice. Trucks inside as well as outside the compound on the road were hit.
But the Obama administration has not yet fully decided how much information it wants to reveal, concerned that it will expose sensitive military intelligence capabilities to the Russians.
What about the the ceasefire?
Monday night's attack came just hours after Syrian authorities declared an end to the fragile ceasefire, which began September 12.
Soon afterward, Syrian warplanes resumed airstrikes in Aleppo, according to the Syrian Observatory for Human Rights, and deadly violence returned across parts of the country.
The events have left the hard-fought ceasefire brokered by Russia and the US in tatters, although US officials said they believe the ceasefire agreement is still in place.
Rhodes, the deputy national security adviser, said the US preference is to continue with the ceasefire effort, paving the way for more cooperation between the Russian and US militaries in Syria, but that Moscow's actions could prevent further coordination.
"We have not seen good faith. This was an outrageous action," Rhodes told CNN's Michelle Kosinski. "It raises serious questions about whether or not this agreement moves forward."
He added, "In conflicts like this I think we have an obligation to continue to pursue whether there are diplomatic openings. If we can't, we walk away."
US Secretary of State John Kerry said before the convoy was struck Monday that any decisions about the ceasefire would be made between Washington and Moscow.
"The Syrians didn't make the deal," he said, "the Russians made the agreement."