The backlash to the proposed merger between the PGA Tour and LIV Golf intensified as Senate Finance Committee Chairman Ron Wyden, D-Oregon, opened an investigation into the deal on Thursday.

The committee will probe the deal between the US-based PGA Tour and the Saudi Public Investment Fund-backed LIV Golf and assess what the deal means for national security.

The PGA Tour's involvement with PIF raises significant questions about whether organizations that tie themselves to an authoritarian regime that has continually undermined the rule of law should continue to enjoy tax-exempt status in the United States, Wyden said in a statement.

Wyden also said he intends to introduce legislation to revoke the Saudi PIF's special tax exemption, which applies to certain foreign investment funds and governments.

The PGA Tour and LIV Golf did not immediately respond to CNN's request for comment.

The PIF, the Saudi sovereign wealth fund, is chaired by Mohammed bin Salman, the Crown Prince of Saudi Arabia. A US intelligence report named Bin Salman as responsible for executing the operation that led to the murder of journalist Jamal Khashoggi in 2018. Bin Salman has denied being involved with Khashoggi's murder.

The surprise deal this month between the PGA Tour and LIV Golf, competing tours locked in a legal battle before the merger announcement, has faced growing opposition from lawmakers.

The Department of Justice has reportedly notified the PGA Tour that its deal is under review for antitrust concerns, according to a report in the Wall Street Journal citing people familiar with the matter.

The reported DOJ probe into the surprise partnership casts doubt over the new, as yet unnamed joint commercial enterprise between the organizations and the Europe-based DP World Tour.

We are confident that once all stakeholders learn more about how the PGA TOUR will lead this new venture, they will understand how it benefits our players, fans, and sport while protecting the American institution of golf, the PGA Tour said in a statement to CNN on Thursday.

The Justice Department had previously opened an investigation into the PGA Tour due to its battle with LIV Golf.

In a letter to the DOJ, Democratic Senators Elizabeth Warren and Ron Wyden wrote that the PGA-LIV deal would make a U.S. organization complicit — and force American golfers and their fans to join this complicity -- in the Saudi regime's latest attempt to sanitize its abuses by pouring funds into major sports leagues.

Earlier this week, the US Senate also opened an investigation into the merger, citing PIF's role as an arm of the Saudi government.

The merger between LIV Golf, PGA Tour and the European DP World Tour shocked fans and players alike.

The US-based PGA Tour said the merger would unify the game and all pending litigation between the tours would be dropped under the new agreement.