A minute's silence was held in Norway at noon local time (1000 GMT) on Monday to remember those killed in Friday's bombing and massacre.
At least 93 people were killed in the massacre at a youth camp on Utoeya island and a bombing in Oslo. It was the worst event in Norway since World War II.
Another 96 were wounded and some are still missing after Anders Behring Breivik systematically gunned them down.
Sweden also held a minute's silence, with both countries flying their flags at half-mast.
Norwegian Prime Minister Jens Stoltenberg observed the minute's silence alongside Norway's royal family at the University of Oslo.
The Royal Palace has announced that one of the victims of the attacks was the brother-in-law of the country's Crown Prince.
The Prime Minister and King Harald V and Queen Sonja were among the mourners in Oslo Cathedral for a memorial mass on Sunday.
''We are gathered under the signs of mourning and of hope,'' said Bishop Ole Christian Kvarme.
Mr Stoltenberg told the congregation that the names and photographs of those who were killed would soon be released and ''the scale of the evil will then emerge''.
This represents a national tragedy, he said.
But despite the tragedy Norway would demonstrate ''more democracy, more openness, more humanity, but without naivety''.
''We are a small country but we are a proud people,'' he said, adding that Norway ''will never abandon its values''.
Hundreds of people gathered earlier outside the cathedral where a shrine has been set up amid a sea of flowers laid in tribute to the dead.