President Trump's relationship with Congress has become more and more strained as he struggles to find legislative wins. Now he's going after Senate Majority Leader Mitch McConnell (R-Ky.), a key leader in his own party. (Jenny Starrs/The Washington Post)

President Trump on Thursday lashed out at Congress for the country's deteriorating relationship with Russia, which he characterized in a tweet as “at an all-time & very dangerous low.”

“You can thank Congress, the same people that can't even give us HCare!” the president said, referencing the failure of the Senate to pass legislation overhauling the Affordable Care Act, a long-term GOP priority and marquee Trump campaign promise.

The president’s assessment came a day after he begrudgingly signed legislation, passed by overwhelming majorities in the House and the Senate, that imposes new sanctions on Russia and places restrictions on his ability to roll back punitive measures already in place.

In a statement Wednesday, Trump criticized the bill he signed as “seriously flawed,” arguing that it encroaches on his powers as president. He also said that he had “built a great company worth many billions of dollars” and asserted that he “can make far better deals with foreign countries than Congress.”

Lawmakers from both parties pushed back against Trump’s tweet Thursday. Those included Sen. Bob Corker (R-Tenn.), chairman of the Foreign Relations Committee, who pinned blame for the deteriorating U.S.-Russia relationship “solely” on Russian President Vladimir Putin.

“I know there’s some frustration. I get it,” Corker said, speaking of Trump's reaction to the sanctions bill. “We acted in the country’s national interest in doing this. Putin, through his actions, is the one who has taken this relationship back to levels we haven’t seen since 1991.”

Those actions, Corker said, include “an affront to the American people” by meddling in last year’s presidential election.

Lawmakers’ solidarity in ­tying Trump’s hands on Russian sanctions reflects a deepening concern about the White House’s posture toward Moscow, which critics have characterized as naive.

President Trump signed a bill imposing new sanctions on Russia on August 2. (Victoria Walker/The Washington Post)

The new Russia sanctions expand on measures taken by the Obama administration to punish the Kremlin for its interference in the election. But Trump has continued to cast doubt that Russia alone was responsible. And he has called investigations by Congress and a special counsel into the allegations — including possible collusion involving the Trump campaign — a “witch hunt.”

Russia this week reacted to Congress’s passage of the sanctions bill, as well as the earlier Obama-imposed measures, by announcing that it would order the U.S. Embassy there to reduce its staff by 755 people and seize U.S. diplomatic properties.

Russian Prime Minister Dmitry Medvedev criticized Trump on Wednesday for signing the bill.

“The Trump administration has shown its total weakness by handing over executive power to Congress in the most humiliating way,” he tweeted.

Trump has sought to build a relationship with Putin, repeatedly asserting that the United States and Russia have shared interests.

During the Group of 20 summit in Germany last month, the two leaders had a much-publicized meeting that ran more than two hours — far longer than scheduled — and chatted informally for up to an hour later that day during a dinner for G-20 leaders.

Thursday’s tweet comes at a time of fraying ties between Trump and Senate Republicans in particular. GOP senators have sought to distance themselves from the president, who has called them “fools” and tried to strong-arm their agenda and browbeat them into changing a venerated rule to make it easier to ram through legislation along party lines.

Among those speaking out about Trump on Thursday were Sen. Jeff Flake (R-Ariz.), who read the president's tweet off a reporter’s phone.

“Huh. Well. It is what it is,” Flake said. Asked whether he agreed with the president, Flake said, “Congress's fault? I don't think so.”

His Republican colleague from Arizona, Sen. John McCain, responded to Trump on Twitter by blaming a different party: “You can thank Putin for attacking our democracy, invading neighbors & threatening our allies,” McCain wrote.

Democrats were also critical of the president’s tweet.

“That shows a continuing lack of understanding by the president of what happened,” said Sen. Mark R. Warner (D-Va.), who earlier tweeted that the blame for the worsening U.S.-Russian relationship rests with Putin.

Michael F. Bennet (D-Colo.), meanwhile, offered this succinct response to Trump’s tweet: “That is ridiculous.”

Abby Phillip and Sean Sullivan contributed to this report.