Tens of thousands of demonstrators in South Korea have held candle-lit vigils in eight cities to protest the impeachment of President Roh Moo-hyun.
A majority of South Koreans are opposed to impeachment
About 35,000 supporters gathered near the US embassy in Seoul chanting "impeachment is null and void".
Supporters of Mr Roh have promised daily protests against Friday's vote in parliament to impeach him.
Polls show 70% believe the main charge of violating electoral law is not serious enough to warrant such a move.
The protests followed similar demonstrations on Saturday, when protesters occupied a central thoroughfare, singing and chanting slogans.
The BBC's Charles Scanlon in Seoul says the scenes were reminiscent of mass anti-American protests in 2002 - a wave of nationalist emotion that helped bring President Roh to office.
Finance Minister Lee Hun-jai is to travel to New York, Hong Kong and London in the next week or two, in an effort to calm the fears of overseas investors.
Meanwhile North Korea expressed concern about the situation and called for the latest round of inter-Korean economic talks be moved from the South to the Northern town of Kaesong.
A political outsider from the left of politics, Mr Roh served only one turbulent year of a five-year term.
WHAT HAPPENS NEXT?
President Roh's powers suspended
Case decided by Constitutional Court, could take six months
PM Goh Kun becomes acting head of state
15 April National Assembly elections to go ahead
Prime Minister Goh Kun has taken over as acting head of state and is trying to restore calm.
He will remain in the role of president until the Constitutional Court rules whether the impeachment was valid.
But South Korea has been left with an unprecedented political vacuum.
Roh Moo-hyun remains the occupier of the presidential Blue House, awaiting a final decision from the Constitutional Court that could take six months.
Mr Goh urged the Constitutional Court to give a ruling as quickly as possible on the legality of the impeachment.
In a televised address he called for calm and urged the court to make its decision as soon as possible.
He promised to continue existing policies on the economy and in foreign affairs.
The government has increased vigilance along the border with the North as a precaution in case the Communist state tries to exploit the crisis.
The defence minister held talks with the commander of US forces in Korea which maintains an infantry division near the front line.
Many analysts believe President Roh will eventually be reinstated by the Constitutional Court.
It is unclear whether it will give its ruling before national assembly elections in the middle of April.