* Treasury pushes back estimate for hitting debt limit
* U.S. says to keep coupon auction sizes steady
* Dealers, Treasury discuss "ultra long" bonds (Adds quote from senator, deficit estimates, background)
By David Lawder
WASHINGTON, Feb 2 The United States will hit a $14.3 trillion statutory limit on its debt slightly later than previously estimated, the Treasury said on Wednesday as it unveiled a still-hefty debt auction schedule.
Treasury officials said the limit would now be hit between April 5 and May 31, versus a previous estimate of end-March to mid-May. The later time frame reflected an upward revision to estimates of tax receipts and a downward revision to projected borrowing from the Social Security and Medicare trust funds.
The officials said they were proceeding with borrowing plans under the assumption Congress will raise the limit without a protracted battle, an assumption financial markets share.
How much it should be raised is a question for Congress, they said.
"We do not have a have particular figure that we have put to Congress. That is their prerogative to offer that," Mary Miller, Treasury assistant secretary for financial markets, told a news conference.
If Congress does not raise the limit in a timely way, the government could be forced to scale back operations. A failure to lift the limit could raise the specter of a first-ever U.S. debt default and push up interest rates sharply.
Financial markets have not yet shown any nervousness over the debt limit, which has typically been raised after political grumbling. Treasury yields rose on Wednesday as higher oil prices fueled inflation concerns, but the 10-year note US10YT=RR remained below 3.5 percent resistance level.
For a Factbox on steps the Treasury can take to avoid hitting the debt ceiling, see [ID:nN02116897]
For a Q&A on the debt limit, see [ID:nN02179154]
Still, there will be political skirmishes along the way.
A number of Republican lawmakers have raised opposition to increasing the limit without significant concessions on spending cuts from the Obama administration. A contentious debate is expected after the White House unveils its proposed fiscal 2012 budget later this month.
"Given the history of debt limit fights, brinkmanship will rule the day, and nothing of significance will happen in February," said Pierpont Securities analyst Stephen Stanley adding that a resolution could drag out "to the bitter end."
Senate Budget Committee Chairman Kent Conrad said the delay in hitting the debt limit buys more time for Congress to reach consensus on a plan to control long-term deficits -- a complex and difficult task.
"The increase in the debt limit, the amount of it, is much less important to me than having a plan that over time brings down this debt," Conrad, a Democrat from North Dakota, told reporters. "That to me is the key."
The Treasury can take special measures such as dipping into government pension funds, to delay hitting the limit by up to another eight weeks, potentially pushing the day of reckoning into July. It plans to provide a new estimate on the timing at the start of every month.
It already has begun to draw down a $200 billion Federal Reserve supplementary financing account, and Miller said the next step would be to halt issuance of debt to state and local governments, which has totaled $36.4 billion since October.
Treasury's Miller said the government had no plans to selectively cut or delay payments to employees or contractors . That "would in a sense be defaulting on our obligations, so it's not a path that we want to go down," she said.
She added that accelerating sales of assets held by the government, such as shares in bailed-out companies or mortgage-backed securities, was also not an option that Treasury wanted to consider.
On Monday, the Treasury slashed its borrowing estimate for the current quarter by $194 billion due to the drawdown of the Fed account.
But overall, it said spending needs are increasing due to the recently enacted package of extended tax cuts and unemployment benefits. The Congressional Budget Office last week estimated a record $1.48 trillion for fiscal 2011, up from $1.29 trillion last year.
The Treasury said it intends to meet this funding increase through a rise in short-term bill auction sizes, while keeping longer-term note and bond auctions steady at current levels.
As expected, the Treasury announced a $72 billion refunding of its maturing 3-year, 10-year and 30-year debt, unchanged from the last refunding in April. The auctions will raise about $50.2 billion in new cash. For details see: [ID:nWAL1DE7YV]
The Treasury also disclosed that it had discussed with big bond dealers the possibility of an "ultra-long" bond with a maturity of 40, 50, or 100 years, as one of several options to broaden the investor base for Treasury debt. Miller said no decisions on this front were imminent. [ID:nN02194927]. (Additional reporting by Rachelle Younglai; Editing by Andrea Ricci and Andrew Hay)