WASHINGTON ― A series of bombshell revelations Wednesday night cast new light on Donald Trump’s potential ties to the Russian government during the course of the presidential campaign and seem likely to escalate calls for a special prosecutor to investigate the matter.

The New York Times reported that intelligence officials working for the Obama administration had grown so concerned about the scope of Russia’s meddling in the elections and the evidence of ties to Trump’s operation that they began to leave a breadcrumb trail of clues for future investigators to follow. Among those data points that had them spooked were a series of meetings that affiliates of the Trump campaign and the Russian government allegedly held in European capitals ― meetings that the Trump White House has consistently denied ever took place.

About an hour later, The Washington Post published its report that U.S. Attorney General Jeff Sessions spoke twice last year with Russia’s ambassador to the United States and failed to disclose it to lawmakers during his January confirmation hearing. Sessions had been a top surrogate for the Trump campaign and a senior member of the influential Senate Armed Services Committee. The newspaper noted that no other member of that committee could recall speaking to the Russian ambassador.

U.S. investigators have looked into Sessions’ communications with the Russian diplomat as part of a broader investigation into possible links between Trump’s campaign and the Russian government, The Wall Street Journal reported later on Wednesday.

Justice Department officials told The Washington Post that Sessions met with Ambassador Sergey Kislyak in his role as a member of the Senate Armed Services Committee rather than as a Trump campaign adviser. (The Post could not identify a member of the committee who had met with Kislyak last year.)

Sessions followed up late Wednesday with a statement: “I never met with any Russian officials to discuss issues of the campaign. I have no idea what this allegation is about. It is false.”

The three articles stoked the fires of a controversy that has roiled Washington and threatened to derail the Trump administration’s agenda just months into the president’s term. The White House and most congressional Republicans have so far resisted calls to appoint a special prosecutor to investigate Russia’s role in the election. But by Wednesday evening, Sen. Lindsey Graham (R-S.C.) was conceding that one might be needed in light of the Sessions revelation.

Graham: If Jeff Sessions spoke with Russian diplomat, “then for sure you need a special prosecutor” #CNNTownHall https://t.co/uY26ChouyB — CNN Politics (@CNNPolitics) March 2, 2017

Rep. Adam Schiff (D-Calif.), the top Democrat on the House Intelligence Committee, said Wednesday that if Sessions met with the Russian ambassador during the campaign and failed to disclose it at his confirmation hearing, it is “essential” that he recuse himself from the investigation. “This is not even a close call; it is a must,” he said in a statement.

House Minority Leader Nancy Pelosi (D-Calif.) accused Sessions of perjury and called on him to step down as attorney general.

“After lying under oath to Congress about his own communications with the Russians ... Sessions is not fit to serve as the top law enforcement officer of our country and must resign,” she said Wednesday night. “There must be an independent, bipartisan, outside commission to investigate the Trump political, personal and financial connections to the Russians.”

Constitutional law expert Laurence Tribe, when asked Wednesday on Twitter for his take on whether this constitutes perjury, responded, “Looks like it to me: it was a knowing & deliberate falsehood made under oath on a clearly pertinent matter.”

Looks like it to me: it was a knowing & deliberate falsehood made under oath on a clearly pertinent matter. https://t.co/5HCXHBySso — Laurence Tribe (@tribelaw) March 2, 2017

How the Justice Department proceeds from here will become more clear in the days ahead. A Sessions spokesman insisted to the Post that the former senator had not lied to the Senate Judiciary Committee when he said, point blank, that he “did not have communications with the Russians” during the campaign. But that spokesperson gave no indication if Sessions would continue playing a role, if any, in the FBI’s investigation into the matter. Sessions, to date, has been ambiguous about whether he will step aside and appoint an independent prosecutor to head the Justice Department’s investigation into alleged communications between members of the president’s campaign team and Moscow.

Here's the video of Sessions denying **under oath** that he had communications with the Russians. pic.twitter.com/YFxCgqjQo6 — CAP Action (@CAPAction) March 2, 2017

On Capitol Hill, the Senate Intelligence Committee has its own ongoing investigation. And even before Wednesday night’s revelations, the House Intelligence Committee announced that it would also look into ties between members of Trump’s campaign team and the Russian government as part of a broader probe into Moscow’s alleged interference in the 2016 election.

The six-page document outlining the full scope of the House Intelligence committee’s investigation remains classified, Chairman Devin Nunes (R-Calif.) and Schiff, the ranking member, said in a statement Wednesday night. But the statement said the probe will focus on the following questions:

What Russian cyber-activity and other active measures were directed against the United States and its allies?

Did the Russian active measures include links between Russia and individuals associated with political campaigns or any other U.S. persons?

What was the U.S. government’s response to these Russian active measures and what do we need to do to protect ourselves and our allies in the future?

What possible leaks of classified information took place related to the Intelligence Community Assessment of these matters?

The outline of the investigation represents a compromise between Democrats, who have pressed for more information about possible ties between the president and the Kremlin, and Republicans, who have sought to downplay the intelligence community’s assessment that Moscow hacked Democratic entities with the aim of helping Trump win the election. Nunes, an ardent Trump supporter, warned Monday against conducting a “witch hunt” against the president and Russia, and he suggested that the committee should focus on rooting out the source of government leaks, which helped bring the scandal to light.

The committee will conduct interviews, take witness testimony and review the material that supported the intelligence community’s January finding that Russian cyber-activity was aimed at boosting Trump’s chances of becoming president. It will also review the intelligence community’s “analytic standards” and investigate the “leaks of classified information,” according to the statement.

Links between the Trump team and Moscow have already sunk one top adviser. Retired Lt. Gen. Michael Flynn was forced to resign as Trump’s national security adviser last month after The Washington Post revealed that he had discussed U.S. sanctions against Moscow with the Russian ambassador to the U.S. before Trump entered the White House ― and subsequently lied to the media and to Vice President Mike Pence about the contents of their discussions.

The House Intelligence panel’s investigation will occur alongside a separate ongoing probe by the Senate Intelligence Committee. But Democrats fear that Republicans, who control both chambers of Congress, could hamstring the inquiries.

“It’s been looked into, and there’s no evidence of anything there. Rep. Devin Nunes (R-Calif.)

Nunes, who was a member of Trump’s transition team, has preemptively dismissed ties between the Trump campaign and Russian intelligence officials. “It’s been looked into, and there’s no evidence of anything there,” he told reporters Monday. Both Nunes and Sen. Richard Burr (R-N.C.), who heads the Senate Intelligence Committee, were recruited by the White House to rebut news stories about Trump-Russia connections.

In addition to the congressional committees and the FBI investigation, Democrats and Republican Russia hawks Graham and Sen. John McCain (Ariz.) have called for a bipartisan select committee to look into Russia’s role in the 2016 campaign. Such a committee would give Democrats a greater ability to subpoena witnesses and preserve records obtained in the investigation. But Republican leadership had resisted those calls, arguing that the intelligence committees were the proper venues.

UPDATE: This post has been updated with information on new reports about investigations into the contact between the Trump campaign and Russia.

CORRECTION: An early version of this post identified Nancy Pelosi as Senate minority leader. She is House minority leader.

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