Leaders of the Senate Intelligence Committee said Wednesday that they are not yet able to determine whether any of the presidential political campaigns colluded with Russia last year, and said so far, it's not clear whether Russia preferred Donald Trump or Hillary Clinton.

Committee Chairman Richard Burr, R-N.C., said the simple question of collusion has not yet been settled despite dozens of interviews and thousands of pages of transcripts to pore over.

"The issue of collusion is still open," Burr said at a press conference. "We continue to investigate both intelligence and witnesses."

He also said that while the committee believes Russia was attempting to influence the election, it's not clear yet who Russia favored.

"Russian involvement in the election process, we're in agreement with that," Burr said. "We have not come to any determination on collusion, or Russia's preferences."

"If we use solely the social media advertising that we have seen, there's no way that you can look at that and say that that was to help the right side of the ideological chart, and not the left, or vice-versa," he added. "They were indiscriminate," Burr said.

Both Burr and ranking member Mark Warner, D-Va., indicated that the committee is unable to set a date for when it would be done with its investigation and reach a conclusion, meaning it could continue for several weeks and possibly several months.

"We're not there yet," Burr said. "I'm not even going to discuss initial findings, because we haven't any."

The committee has interviewed more than 100 people resulting in more than 250 hours of transcripts and more than 4,000 transcript pages since it began its investigation in January, Burr said.

There have also been more than 100,000 pages of documents to review, including highly classified intelligence reports, emails and campaign documents, Burr told reporters.

The committee has also interviewed "everyone" who had a hand in compiling the intelligence community's assessment about Russian interference, as well as officials from the Obama administration. The committee has also interviewed everyone who contributed to drafting the Trump presidential campaign platform, Burr revealed.

Burr said because of this, "It's safe to say the inquiry has expanded," adding the committee has 25 more interviews scheduled this month.

"It is taking a long time. But getting it right and getting all the facts is what we owe the American people," said Warner.