Donald Trump has called a recent CIA assessment of Russian hacking "ridiculous".
The CIA had concluded with "high confidence" that Russia sought to influence the US presidential election on behalf of Mr Trump.
Mr Trump also says he is not interested in getting daily intelligence briefings - an unprecedented move. The president-elect's remarks followed demands for a bi-partisan investigation into the Kremlin's activities.
Questions have also been raised about his consideration of Exxon Mobil CEO Rex Tillerson, who has close business ties with Moscow, as head of the State Department.
Branding the CIA's conclusion that Russia tried to interfere with the presidential election as ridiculous, Mr Trump blamed "very embarrassed" Democrats for the public release of the assessment.
But he said he does not necessarily oppose President Obama's order for a review of campaign-season hacking. "If you're going to do that, I think you should not just say 'Russia'. You should say other countries also, and maybe other individuals."