President Trump said Thursday that he knew nothing about his former campaign chairman, Paul Manafort, allegedly sharing 2016 presidential campaign polling data with Konstantin Kilimnik, an associate the FBI has said has ties to Russian intelligence.

That information was included in a court filing this week that appeared to inadvertently include details not intended to be made public and indicates a pathway by which the Russians could have had access to Trump campaign data.

“No I didn’t know anything about it,” Trump said in response to a question from a reporter as he departed the White House en route to Texas, where he is visiting the U.S.-Mexico border. Trump did not elaborate and turned to another reporter with a question on a different topic.

Trump’s response comes as special counsel Robert S. Mueller III continues to probe whether there was coordination between Russia and the Trump campaign.

Manafort on Tuesday denied in a filing from his defense team that he broke his plea deal by lying repeatedly to prosecutors working for Mueller about that and other issues.

In his rebuttal to the special counsel’s claims of dishonesty, Manafort exposed details of the dispute, much of which centers on his relationship with Kilimnik. The Russian citizen, who began working for Manafort’s consulting firm starting in 2005, has been charged with helping his former boss to obstruct Mueller’s investigation of Russian interference into the 2016 election. He is believed to be in Moscow.

The special counsel alleged Manafort “lied about sharing polling data with Mr. Kilimnik related to the 2016 presidential campaign,” according to the unredacted filing. The source of that data, including whether it came from the Trump campaign, is unclear.

Rachel Weiner, Spencer S. Hsu and Rosalind S. Helderman contributed to this report.