Jacob Lew.

U.S. President Barack Obama was expected to nominate his chief of staff, Jack Lew, as the next U.S. treasury secretary on Thursday. Lew is an Orthodox Jew and one of Obama’s closest advisers. The Lew appointment comes on the heels of Obama’s selection of John Kerry as Secretary of State and the controversial Chuck Hagel for Secretary of Defense.

White House Press Secretary Jay Carney praised the expected nominee Lew: “Over the past more than quarter of a century, Jack Lew has been an integral part of some of the most important budgetary financial and fiscal agreements, bipartisan agreements in Washington.” As treasury secretary, Lew will jump straight into the fire of a tough battle against Republicans in Congress over the deficit ceiling and extensive cuts to government spending.

Obama’s choice of Lew is seen as a signal of the president’s determination to control record-breaking budget deficits. The 57-year-old Lew would bring private sector and international experience to the Treasury Department. He has held top jobs at Citigroup’s wealth management branch and at the State Department, where he oversaw international economic issues in his first job for Obama.

A person familiar with the selection process said Lew’s budget experience was particularly important to the president, given the treasury secretary’s key role in coordinating with European allies on the continent’s debt crisis, among other global financial matters. Assuming that Lew is confirmed by the Senate, he will replace Treasury Secretary Timothy Geithner, the last of Obama’s original economic team of 2008.