US congress is expected to pass a $789bn economic stimulus package backed by Barack Obama, the US president, after days of negotiation and partisan wrangling.

The US House of Representatives is expected to vote at around 1pm to 2pm local time (1800 to 1900GMT) while the senate is likely to vote in the evening, although this has not been confirmed.

Members of the house and senate from both the Republican and Democrat parties forged an agreement on the deal on Wednesday following long-drawn-out talks.

Obama had urged the Democratic-controlled congress to pass the stimulus bill before the end of the coming holiday weekend so he can sign it into law.

The stimulus package, reduced from its original size of around $937bn, aims to cut taxes for the US middle class, boost construction projects and create up to four million new jobs.

Most Republicans, and some moderate Democrats, had opposed the stimulus plan, arguing it expanded government spending too much and did not include enough tax cuts needed to boost the economy.

No 'miracle cure'

Obama described on Thursday the stimulus package as essential to turn around the US economy, which has been buffetted by the subprime mortgage crisis, tight credit, failing banks and the global economic slowdown.

"Right now, we have a once in a generation chance to act boldly, to turn adversity into opportunity, and use this crisis as a chance to transform our economy for the 21st century," he said.

"That is the driving purpose of the recovery and reinvestment plan."

However, Lawrence Summers, director of the White House National Economic Council, told NBC on Friday that the stimulus package is not some "miracle cure" or "silver bullet" for the economy.

I think this is a key part of what's gong to be a multipart strategy to contain this decline," he said.

"[The problems] weren't made in a week, a month, a year. It's going to take time to fix."