WASHINGTON – The investigation into whether the Trump campaign colluded with Russia to win the 2016 presidential election continues, at the peril of the GOP agenda.

Did President Trump try to block the investigation into Russia's attempts to interfere with the election?

That's one of the questions the Senate Intelligence Committee is trying to answer.

"No collusion, no obstruction," Trump insisted at a news conference on Friday.

Trump is doubling down, telling reporters he did not try to pressure former FBI Director James Comey's investigation into Michael Flynn, something Comey disputed last week on the stand.

Democrats and Republicans have called on Trump to release any tapes, if they exist, of conversations he had with Comey.

Jay Sekulow of the American Center for Law and Justice is a member of Trump's legal team.

"The president said he is going to address the issue of the tapes, whether the tapes exist or not, next week," Sekulow said Sunday on ABC's This Week with George Stephanopoulos, adding, "that's a decision that the president will make in consultation with his chief lawyer Marc Kasowitz."

Over the weekend, Trump blasted Comey on Twitter.

"I believe the James Comey leaks will be far more prevalent than anyone ever thought possible. Totally illegal? Very 'cowardly!'" he wrote.

Some senators like Lindsay Graham, R-SC, say Trump should lay off the tweets.

"You're your own worst enemy. Knock it off," said Graham on "This Week."

Sen. Mike Lee, R-Utah, says he hasn't seen any evidence whatsoever that the Trump campaign colluded with Russia.

Many of these Republicans worry about the ticking legislative clock and how it's slowing down the party's agenda.

Trump sees it too and is trying to shift the focus.

"We want to get back to running our great country," he said Friday.

But the investigation isn't going away and is only ramping up.

Special Counsel Robert Mueller is putting together a first-rate legal team to dig deeper, and more hearings are coming on Capitol Hill.

Attorney General Jeff Sessions, who recused himself from the investigation after acknowledging he met with the Russian ambassador to the U.S., will testify Tuesday.

Lawmakers also hope to hear from President Obama's attorney general, Loretta Lynch, who Comey accused of trying to help Hillary Clinton with the probe into her emails by asking him to call it a "matter" instead of an "investigation."

Despite the distractions from the Russia controversy, the Senate does have a bright spot: it looks like there could finally be some movement on healthcare reform.

"The Hill" reports a path is emerging for Senate Republicans to pass their bill to repeal and replace ObamaCare, as some moderates may compromise on Medicaid funding, removing one of the biggest obstacles for the bill.

But it's going to take time and this looming Russia investigation doesn't help.

The question is this: how much will it continue to slow down the entire conservative agenda?