Since winning reelection, President Barack Obama has announced new choices to head the State Department, Pentagon and Central Intelligence Agency.

But he has yet to act on another looming top-tier vacancy, that of Treasury secretary.

Indications are now that Timothy Geithner will leave that post by the end of the month, regardless of whether the president and Congress have reached a deal on the debt ceiling -- the next potential economic crisis facing the government.

Given the pace of recent negotiations, it's a safe bet that they won't.

Geithner has been trying to leave since 2011. But until now, Obama has persuaded him to stay to help deal with one tense budget crisis after another, most recently the barely averted "fiscal cliff."

A last-minute deal approved by Congress on New Year's Day and quickly signed by Obama blocked hundreds of billions of dollars of automatic tax increases and spending cuts from taking effect.

That cleared the way for Geithner's departure.

White House chief of staff Jack Lew is likely to get the nomination. He was budget director for both Obama and President Bill Clinton and a managing director for Citigroup (NYSE:C). He is well versed on financial issues that Treasury secretaries must confront.

Geithner has suggested he hopes to leave "around" the inauguration, now just two weeks away.

White House spokesman Jay Carney is providing no timetable on when Obama will act. But he says that when the president does, "he will look forward to speedy consideration by the Senate."

The clock is ticking, since Treasury officials say they'll run out of money to pay all the government's obligations sometime in February or March if Congress doesn't raise the current $16.4 trillion limit on borrowing authority.

Republicans say they will demand major spending cuts in exchange for any agreement to raise the debt limit. Obama says he won't negotiate on the debt limit, period.

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