Russia has denied claims its intelligence agencies have compromising material about Donald Trump.
Dmitry Peskov, President Vladimir Putin's spokesman, said the allegations were "pulp fiction" and a "clear attempt to damage relations".
The unsubstantiated claims say his presidential campaign secretly communicated with Moscow. They also say Russia has information about the US president-elect involving prostitutes.
Mr Trump has condemned the reports.
The president-elect tweeted: "FAKE NEWS - A TOTAL POLITICAL WITCH HUNT!"
Later on Wednesday, he went on to write: "Russia has never tried to use leverage over me. I HAVE NOTHING TO DO WITH RUSSIA - NO DEALS, NO LOANS, NO NOTHING!"
Mr Trump is due to hold a news conference on Wednesday, nine days before he takes office.