After the August attack, Ukraine had denied involvement in the killing while Russia's Federal Security Service accused Ukraine's secret services of being behind it.
United States intelligence agencies believe parts of the Ukrainian government approved a car bomb attack near Moscow in August that killed Darya Dugina, the daughter of a prominent Russian nationalist, the New York Times has reported, citing unidentified officials.
The United States took no part in the attack on Dugina and was not aware of it ahead of time, the Times reported.
American officials admonished Ukrainian officials over the assassination, the Times said.
After the attack, Ukraine denied involvement in the killing while Russia's Federal Security Service accused Ukraine's secret services of being behind it.
Russia had also accused Ukraine
The Kremlin said on Thursday Russian intelligence had always argued that Ukraine was behind the killing.
Asked about the Times report, Kremlin spokesperson Dmitry Peskov told reporters it was "positive" that the US appeared to agree with Moscow about Ukraine's alleged involvement in the assassination.
The Times quoted a Ukrainian presidential adviser, Mykhailo Podolyak, as repeating the denial that Kiev was behind the attack.
On Thursday, Kiev once again rejected the claims it was involved in the attack.