In an off-camera news briefing on May 27, national security adviser H.R. McMaster was asked about President Trump's senior adviser and son-in-law, Jared Kushner seeking to set up a secret communications channel between Trump's transition team and the Kremlin. (Reuters)

TAORMINA, Italy — President Trump's national security adviser, H.R. McMaster, said Saturday he "would not be concerned" about having a back-channel communications system with Russia, though he and other top White House officials refused to comment specifically on the growing controversy surrounding Jared Kushner.

A news briefing here at the conclusion of Trump's maiden foreign trip was overtaken at times by questions about Kushner, the president's son-in-law and senior adviser, and Friday's Washington Post report that Kushner had discussed the possibility of setting up a secret and secure communications channel between the Trump transition team and the Kremlin.

The Post reported earlier in the week that Kushner — who helped plan the Middle East portion of Trump's trip and traveled with the president to Saudi Arabia, Israel and the Vatican — is now a focus of the FBI investigation into Russia's meddling in the 2016 presidential election.

McMaster and National Economic Council Director Gary Cohn, who together briefed reporters Saturday, were unwilling to discuss the Kushner matter, as was White House press secretary Sean Spicer. White House officials insisted the briefing be conducted off-camera, preventing photographers or television cameras from documenting it.

As McMaster and Cohn took the stage in the briefing room, a television screen just over their shoulder played CNN, which at that moment aired a discussion of the Kushner-Russia story under a "breaking news" banner.

"We're not going to comment on Jared," Cohn said. "We're just not going to comment."

McMaster said he could not talk about Kushner's talks with Russia because "it's not something that I've in any way been involved with or that I have any knowledge of."

McMaster, a decorated three-star Army general, was asked whether he would be concerned if an official on his National Security Council staff or elsewhere in the Trump administration sought a back-channel communications system with the Russian embassy or the Kremlin in Moscow.

"No," McMaster said. "We have back-channel communications with a number of countries. So, generally speaking, about back-channel communications, what that allows you to do is to communicate in a discreet manner."

He continued, "No, I would not be concerned about it."

The press briefing grew tense, in part because Trump has refused to hold a news conference of his own or answer questions in an extended format with journalists during his marathon foreign trip. U.S. presidents traditionally hold news conferences when they travel overseas.

Cohn defended Trump's decision to evade the news media, citing the president's "robust" travel schedule.

"The president, since he left New York [he later corrected himself to say Washington] has been dealing with foreign leaders, he's been dealing with jobs, he's been dealing with economic growth, he's been dealing with diplomacy, he's been dealing with unfair trade, he's been dealing with Paris [climate agreement], he's been dealing with China," Cohn said. "His agenda has been overflowing. He's been fully consumed with what's going on here."

Still, the Kushner questions persisted. When the first one was raised, McMaster punted it to Spicer.

"I'll ask Sean to cover that later," McMaster said.

Spicer, seated in the corner of the room, interjected, "We have nothing."

Indeed, once McMaster and Cohn called an end to their briefing, which lasted about a half-hour, Spicer and other administration spokespeople hurried out of the room.

Sergey Kislyak reported to his superiors in December that Jared Kushner, President Trump's son-in-law and adviser, asked him about setting up a communications channel between the transition team and the Kremlin using Russian facilities in the United States. (Alice Li,McKenna Ewen/The Washington Post)