US President Barack Obama on Thursday announced his new pick to head the Internal Revenue Service after a scandal at the tax agency over the inappropriate targeting of conservative groups. The nomination of John Koskinen, who directed government mortgage giant Freddie Mac in the wake of the 2008 financial crisis, requires confirmation by the Senate, where Obama\'s Republican critics are in the minority but could still throw up roadblocks to the nomination. \"John is an expert at turning around institutions in need of reform,\" Obama said in a statement. \"With decades of experience in both the private and public sectors, John knows how to lead in difficult times, whether that means ensuring new management or implementing new checks and balances.\" The integrity of the IRS was called into question in May when some of its agents were found to have singled out conservative groups for excessive scrutiny as they applied for non-profit, tax-exempt status. Critics of the institution argue that the scandal has yet to be resolved. \"I am confident that John will do whatever it takes to restore the public\'s trust in the agency,\" Obama said on Thursday. The US president initially called the agency\'s behavior \"intolerable and inexcusable,\" and the White House acknowledged errors in IRS actions. After months of intense criticism about the tax agency and other issues including the administration\'s handling of a deadly attack on the US mission in Libya, the president in recent days has dismissed such distractions as \"phony scandals.\" Orrin Hatch, the top Republican on the Senate Finance Committee, said Koskinen would be fairly considered, but hinted at a tough nominations fight as he lashed out at the White House for failing to take appropriate action over the IRS scandal. \"My response is that I will not stop until the truth comes out and I will demand significant answers from this nominee to ensure that we not only get to the truth, but that the administration is fully cooperating with our efforts.\" The Senate begins its annual summer recess this weekend, and hearings to consider Koskinen\'s nomination are likely in September.