U.S. Treasury officials have repeated their warning that Washington has until August 2 to raise the nation’s debt ceiling or face “catastrophic” economic consequences.

Friday’s reiteration of the deadline follows news reports that the practical deadline is earlier, in late July, to give Congress time to debate and vote on the debt limit.

The White House and congressional Democrats have been negotiating with Republicans to reduce this year’s $1.4 trillion budget deficit in exchange for raising the debt ceiling. Talks broke down last week after Republican lawmakers walked out of negotiations chaired by Vice President Joseph Biden.

The U.S. government will continue to collect revenue after August 2, but it will not be enough to meet tens of billions of dollars in expenses that come due at that time. The shortfall between government revenue and government expenses has been running more than $100 billion a month, a gap that has been closed by borrowing.

Washington has run up a total debt of $14.3 trillion and can not borrow more unless congress raises the legal limit on borrowing.

The debt ceiling has been raised many times in the past, but right now opposition Republicans say they want to see drastic cuts in spending before they vote to increase the debt limit. President Barack Obama and his Democratic party allies in congress are also calling for sharp spending cuts, but want to also raise some taxes on wealthy Americans, oil companies and some others to help close the deficit.

Talks between the two sides have not worked out the differences, prompting leaders of the Democratically-controlled Senate to cancel the normal Independence Day recess. Republicans control the House of Representatives and are scheduled to end their holiday next week.

A news report says Mr. Obama and Senate Democrats are considering a short-term increase on the U.S. debt ceiling to cover the nation’s borrowing needs for seven months.