By Charles Scanlon
BBC correspondent in Seoul
The acting president of South Korea has called for calm following the impeachment of President Roh Moo-hyun.
Goh Kun asked the Constitutional Court to rule quickly
Goh Kun urged the Constitutional Court to give a ruling as quickly as possible on the legality of the impeachment.
Thousands of the president's supporters rallied outside parliament on Friday night and further demonstrations are planned for Saturday.
Polls indicate 70% of the population disagreed with the national assembly's move against him.
South Koreans were stunned by the impeachment of President Roh, who was just one year into his five-year term in office.
Many believe the main allegation that he had broken electoral rules was too trivial to justify impeachment.
Some of the president's supporters are describing the vote in the national assembly as a coup d'etat.
Thousands joined demonstrations across the country and more rallies are planned for Saturday.
Prime Minister Goh Kun has assumed the role of president until the Constitutional Court rules whether the impeachment was valid.
In a televised address he called for calm and urged the court to make its decision as soon as possible.
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
He promised to continue existing policies on the economy and in foreign affairs.
The government has increased vigilance along the border with North Korea as a precaution in case the Communist state tries to exploit the crisis.
The defence minister held talks with the commander of United States 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.