The United States seeks to help its allies prevent Russia from meddling as it allegedly did in the US 2016 presidential election, says House Speaker Paul Ryan.
The Wisconsin representative, who is leading a bipartisan delegation on a tour of NATO allies across Europe, made the comments during a joint press conference with Estonian Prime Minister Juri Ratas in the capital Tallinn.
"One thing we know for certain is that Russia meddled in our election," he claimed. "This is a foreign country trying to meddle within the internal activities of a sovereign country or a democracy."
In a declassified report released in January, the US intelligence community concluded that Russian President Vladimir Putin helped now-President Donald Trump win the White House, an allegation dismissed both by Moscow and the American commander in chief.
The allegation triggered three probes into the matter by the US House, Senate and the Federal Bureau of Investigation.
"What we're doing through our investigation process is to figure out exactly what is it they did and how they did it so that we can help, equip and assist our allies to prevent the same kind of thing happening to them," said Ryan, who was supposed to meet with Estonian President Kersti Kaljulaid later in the day.
Since he started campaigning, Trump has been an opponent of the NATO, arguing that allies are not paying their fair share to enjoy US protection. The president recently made a U-turn on his anti-NATO policy during a visit by NATO Secretary General Jens Stoltenberg to the White House.
Estonia, which has a nearly 300-kilometer border with Russia, spends two percent of its GDP on defense.
The former Soviet republic, which gained independence in 1991, does not have good ties with Moscow.
Russia, meanwhile, has been a staunch opponent of increasing NATO activities in Europe.