Sri Lanka will enforce a state of emergency from midnight on Monday in the wake of the deadly Easter blasts that killed 290 people and wounded more than 500 others, enhancing the counter terrorism powers of the security forces.
The decision was made during a meeting of the National Security Council (NSC) chaired by President Maithripala Sirisena.
The NSC has announced plans to impose a "conditional state of emergency" from midnight, said a statement from the president's media unit.
It said the measures would target terrorism and would not limit freedom of expression.
"These will be limited to counter terrorism regulations. This is being done to allow the police and the three forces to ensure public security," the statement said.
Emergency regulations would give police sweeping powers to deal with situations of breaches of security.
The government also declared on Tuesday as a national day of mourning.
According to the statement, Sirisena will seek international assistance to combat terrorism in the island nation.
The intelligence unit has pointed out support of international terror groups behind the local terrorists, suspected of plotting the deadly Easter blasts. "The international assistance would be sought to combat them," the statement said.