Henry Paulson, the US treasury secretary, will give testimony to the senate banking committee on Tuesday, where he expected to repeat his argument that the bail-out will prove cheaper for taxpayers than leaving companies to suffer the cost of the crisis themselves.
Some critics have expressed concerns over the unprecedented power that the plan would give Paulson and the US government in the financial markets, and whether it would find itself saddled with a gigantic debt.
But George Bush, the US president, pushed congress for progress on Monday, warning that "failure to act would have broad consequences far beyond Wall Street".
Dana Perino, the White House spokeswoman, said that Bush would make the case that the US has taken "aggressive, decisive action" on the situation when he meets world leaders at the UN General Assembly in New York later on Tuesday.
The scramble to steady the US financial ship has left one man with enormous power to steer its course, with some already calling Henry Paulson, the treasury secretary, King Henry.
Paulson had the same powers as his predecessors until a couple of weeks ago: oversight of the government's taxation and fiscal policies.
But as the financial storm erupted, with some institutions crumbling, sold or bailed out, Paulson's new job description has changed substantially.
If approved by congress, his rescue plan would give him sole control of a $700bn line of credit, and the power to use it to take on any bad mortgage-related debt he chooses.
Congress, and the two main presidential candidates, John McCain and Barack Obama, have called for greater oversight of such powers.
Al Jazeera's John Terrett, reporting from New York, said investors were not convinced that the plan was big enough or that the proposal would be approved in time or would work.
Investors fear that the government will have to dramatically ramp up borrowing to pay for the mammoth rescue effort, an inflationary move that could further devalue the dollar and trigger another surge in commodities prices.
Traders shunned the US stock market on Monday and as investors moved their money into tangible assets such as oil and gold, causing commodities prices to surge.
Oil prices jumped more than $25 a barrel to $120.92, recording their biggest ever one-day gain before falling early on Tuesday to $107.24.
Japanese markets were closed on Tuesday for a national holiday but share prices in Hong Kong, Australia, South Korea and Singapore were all lower in early trading.
The FTSEurofirst 300 index of top European shares was down 1.8 per cent at around 09:00 GMT on Tuesday, with banks the biggest drag on the index.
London's FTSE 100 was down 0.08 per cent, Frankfurt's DAX 30 shed 0.26 per cent and the CAC 40 in Paris down 0.62 per cent.
"The bail-out plans are coming under severe pressure now and there are more concerns surfacing then questions being answered. What we're going to need is a little more clarity," James Hughes, market analyst at CMC Markets in London, said.
"Something needs to be said, which is going to calm markets down a little bit and that should start to stabilise things a little bit."
Meanwhile, Nicolas Sarkozy, the French president, said that those responsible for the crisis in the global financial markets should be punished.
In an acceptance speech at an award ceremony attended by US and French business leaders, Sarkozy called for the "truth" on the crisis to be uncovered.
"Today, millions of people across the world fear for their savings, for their apartment, for the funds they have put in banks. It is our duty to give them clear answers," he said.
"Who is responsible for this disaster? May those who are responsible be punished and held accountable."