His speech was broadcast on Twitter by the US Department of State.
"We see that authoritarianism did not die in 1989 or 1991 ... I believe that the US friends in the Czech Republic understand this too," Pompeo said.
He noted that the experience of the Czech Republic shows what threats other states face.
"Russia continues to try to undermine your democracy and your security through disinformation campaigns and cyberattacks, even trying to rewrite your history," the US Secretary of State said.
He also pledged the United States' continued support for "freedom and democracy throughout the world."
In early June, the Czech Republic declared two employees of the Russian Embassy persona non grata in connection with the publication in the Czech media of an article about the alleged transportation of a poisonous substance ricin to the republic.
Russia retaliated.