The US has said the decision to grant political asylum to Chechen separatist Ilyas Akhmadov - whom Russia regards as a terrorist - was not a policy change.
Mr Akhmadov fled to the US two years ago
US state department spokesman Adam Ereli said asylum decisions in the US were made by the courts.
He said the US supported Russia's sovereignty over Chechnya and did not recognise the legitimacy of the separatist Chechen government.
Moscow had said the asylum decision was a "sign of US double standards".
Mr Akhmadov, who fled to the US two years ago - was foreign minister in the separatist Chechen government of Aslan Maskhadov, which was overthrown by Russian forces in 1999.
Observers say Russia has repeatedly failed to convince foreign governments to extradite alleged extremists.
Mr Akhmadov is the latest representative of the separatist Chechen leadership to be granted asylum in a foreign country.
Former President Maskhadov's government dispersed and went into hiding following the Russian decision to send troops back into Chechnya in 1999.
Mr Akhmadov fled to the US two years ago and was granted asylum after security officials dropped objections.
Earlier this year, Mr Maskhadov's representative, Akhmed Zakayev, was granted asylum in the UK, which also angered Moscow.