Rep. Barbara Comstock (R-Va) at an appearance on Oct. 6, 2016, in Lansdowne, Va. (Jahi Chikwendiu/The Washington Post)

Rep. Barbara Comstock (R-Va), increasingly critical of President Trump, joined Democrats and some Republicans Tuesday in demanding that the White House brief Congress on what highly classified information the president disclosed to Russian diplomats.

“Once again we are faced with inexplicable stories coming from the White House that are highly troubling,” Comstock said in a statement about the information President Trump acknowledged sharing last week with Russia’s foreign minister that may have jeopardized a critical source of intelligence on the Islamic State.

“We need to have immediate classified briefings on what occurred at this meeting so that Congress can at least know as much as Russian leaders and know the impact on our national security, our allies, and our men and women protecting our country,” she wrote.

Comstock, who is facing a competitive race for reelection in 2018, had already broken ranks with the Trump administration over last week’s firing of FBI director James B. Comey and the ongoing investigation into whether Russia meddled in the 2016 election.

She was also among just a handful of House Republicans who voted against the latest version of the American Healthcare Act to overhaul the current health care system.

“Both Democrats and Republicans attacked the FBI Director at various times for various reasons and called for his ouster,” she said in a statement about Comey’s termination. “However, I can’t defend or explain tonight’s actions or timing of the firing of FBI Director James Comey.”

About Russia and the election, she said: “There must be an independent investigation that the American people can trust.”

In an interview last week, Comstock said she believes that the FBI and Senate probes into any Russian ties to the administration should continue before a special commission is considered.

Comstock has mostly steered clear of Trump, but has delivered some criticisms — most notably when she called the language he used about women recorded in an “Access Hollywood” video leaked to The Post last October “disgusting” and “vile.”

But Democrats called her more recent stances against Trump political posturing, arguing that she hasn’t taken any action that would lead to an independent investigation into Russia’s role in the presidential election.

“Instead of holding President Trump accountable for his reckless and dangerous decision to share code word classified information with a foreign adversary, Representative Comstock just wants to make sure she knows as much as the Russians do,” said Cole Leiter, spokesman for the Democratic Congressional Campaign Committee. “Comstock either doesn’t understand the gravity of what President Trump did or she’s more interested in political posturing than holding the President accountable.”

Comstock faces increasing competition from Democrats out to stop her from winning a third term in a Northern Virginia congressional district that has become increasingly moderate.

The 10th congressional district spans the Washington suburbs and conservative counties on the West Virginia border. Comstock won reelection last November by 6 points, but her constituents favored Hillary Clinton over Trump by a 10-point margin, making the district one of Democrats’ top targets for next year.

Five Democrats have announced plans to run in their party’s primary for the chance to oppose Comstock. State Sen. Jennifer Wexton, a former prosecutor; Lindsey Davis Stover, a former Obama administration official; Dan Helmer, an Army veteran; Kimberly Adams, past president of the Fairfax teachers union, and David B. Hanson, a retired Naval intelligence officer from Clifton, have announced their campaigns.