It's not as significant as if, say, President Obama were to do it, but Sen. John McCain (R-Ariz.) is set to write an op-ed for the Russian newspaper Pravda, according to Foreign Policy:
In a first-of-its kind arrangement, the editors of Russian newspaper Pravda have tentatively agreed to publish a column by Sen. John McCain that will attack the leadership of Russian President Vladimir Putin. The agreement comes one day after Putin criticized the United States in a widely-read column in The New York Times.