(CNN) – The Obama administration will formally ask Congress later this week to raise the nation’s debt ceiling by $1.2 trillion, a Treasury Department official tells CNN.

The latest request is the third of three requests authorized by the contentious debt ceiling agreement reached last August and is expected to come on December 30 – the day the debt is projected to fall within $100 billion of the current $15.194 trillion ceiling. The new request asks the ceiling be raised to $16.39 trillion.

According to the terms of the debt ceiling agreement, Congress has 15 days to pass a joint resolution disapproving of an increase which President Obama is authorized to veto.

The new debt ceiling is expected to satisfy U.S. debts until the end of next year, according to the Treasury Department official.