(Recasts lead with Monday meeting, adds details)

By Donna Smith

WASHINGTON, Jan 2 (Reuters) - Both President-elect Barack Obama and Vice President-elect Joe Biden will huddle with Democratic and Republican congressional leaders on Monday to try to advance a huge economic stimulus bill that Obama hopes can be enacted quickly, despite Republican reservations.

Leadership aides in Congress said the meeting is set to begin around 3 p.m. EST (2000 GMT) on Monday.

But in the runup to the meeting, Republicans on Capitol Hill were warning their Democratic counterparts that legislation to improve the worsening U.S. economy should not spend too much money on government-funded projects and should not be rushed through Congress without adequate review.

Democrats have been hoping to deliver the plan -- which could cost $675 billion to $775 billion or more -- to Obama on Jan. 20, the day he becomes president, or shortly thereafter.

The newly elected Congress is to be sworn in on Tuesday -- two weeks before Obama. Hearings could push a final package well into February.

The Democrats, who have a majority in Congress, want the economic stimulus to include tax relief for the middle class and spending on schools, roads and other infrastructure. States, which increasingly are having difficulties paying health care costs for the poor, also would get federal money.

But Republicans have voiced concern about possible waste and say the tab could reach $1 trillion.