Twitter plans to notify users who may have [seen] content tweeted during the 2016 U.S. presidential race by accounts connected to the Internet Research Agency, a St. Petersburg "troll farm" implicated in Russia's alleged election meddling.

"We will be working to identify and inform individually the users who may have been exposed to the IRA accounts during the election," Twitter's director of public policy, Carlos Monje, said in congressional testimony Wednesday on Capitol Hill.

"We will be rolling out our response shortly," Mr. Monje told members of the Senate Commerce, Science and Technology Committee.

Professional internet trolls employed by the IRA operated social media accounts on multiple platforms during the 2016 race as part of a state-sponsored interference campaign authorized by Russian President Vladimir Putin, U.S. intelligence officials previously concluded.

Twitter last year identified and suspended 2,752 accounts operated by the IRA, including @Ten_GOP, a purported Republican Party account whose tweets were shared by at least two members of President Trump's 2016 campaign: Kellyanne Conway, the president's campaign manager-turned-counselor, and Gen. Michael Flynn, his ousted former national security adviser.

Less than 10 months until the next general election, Mr. Monje was asked whether Twitter is prepared to protect against any further foreign election interference.

"Based on results, you're not where you need to be for us to be reassured you're securing our democracy," asked Sen. Brian Schatz, Hawaii Democrat. "How can we know that you're going to get this right -- and before the midterms?"

"We're continuing to improve our tools and we're going to get better," Mr. Monje responded.

Twitter's plan to notify users exposed to Russian trolls comes on the heels of Facebook releasing a tool last month that lets account holders see whether they followed any IRA-linked profiles. Facebook previously determined that IRA accounts posted roughly 80,000 posts published between 2015 and 2017, the likes of which were viewed by roughly 140 million users.

"After months of pushing Twitter to do the right thing, I'm encouraged the company will soon notify users who saw content from Kremlin-backed trolls," said Virginia Sen. Mark Warner, the ranking Democrat on the Senate Intelligence Committee, one of four congressional panels currently probing Russia's involvement in the 2016 race.

Russia has denied meddling in the 2016 presidential election.