The US Department of Justice is to investigate the planned partnership between the PGA Tour and the Saudi Public Investment Fund (PIF), which owns LIV Golf, over antitrust concerns, according to 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 commercial enterprise between the organizations and the Europe-based DP World Tour.

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

On Thursday, Senate Finance Committee Chairman Ron Wyden (D-OR) sent a letter to PGA Tour leadership asking a variety of questions to seek clarification and evidence associated with the deal.

Earlier this week, Wyden and fellow Democratic senator Elizabeth Warren called on the Justice Department’s antitrust division to inspect the controversial partnership, saying it would allow Saudi Arabia to “sportswash” its “egregious human rights record” and would violate multiple provisions of antitrust law.