President Donald Trump slammed Democrats for what he called "laughing" over the Russia investigations while attacking fellow Republicans for doing "very little" to protect him, in a pair of new tweets Sunday afternoon.

The president repeated his assertion that the probes are a "Witch Hunt."

"Two groups are laughing at this excuse for a lost election taking hold, Democrats and Russians," he tweeted.

Trump also had some choice words for the GOP.

"It's very sad that Republicans, even some that were carried over the line on my back, do very little to protect their President," he wrote.

Trump, some of his family members and his associates are under investigation by Special Counsel Robert Mueller, the FBI and separate Congressional panels looking into potential collusion between his campaign and the Russian government.

U.S. intelligence agencies have already concluded that Russia used a combination of hacking and disinformation to influence the 2016 presidential election to boost Trump's candidacy and damage Hillary Clinton's.

Congressional lawmakers say Trump's eldest son and his former campaign chairman won't be forced to testify publicly next week as part of the investigations. Donald Trump Jr. and Paul Manafort are discussing undergoing a private interview with the Senate Judiciary Committee. The committee's chairman, Sen. Chuck Grassley, R-Iowa, and top Democrat, Sen. Dianne Feinstein of California, also say they are negotiating with Trump Jr. and Manafort about possibly turning over documents.

Jared Kushner, Trump's son-in-law and top White House aide, is scheduled to speak behind closed doors with the Senate intelligence committee on Monday and the House intelligence committee on Tuesday.

Later in the day, the president directed his Twitter anger at the New York Times and Washington Post, and pressured Republicans again to pass a replacement to ObamaCare.

"It's hard to read the Failing New York Times or the Amazon Washington Post because every story/opinion, even if should be positive, is bad!" the president tweeted Sunday night. Amazon.com CEO Jeff Bezos created the holding company that owns the Post.

"If Republicans don't Repeal and Replace the disastrous ObamaCare, the repercussions will be far greater than any of them understand!" Trump also wrote.