The deadly attacks in Norway, which claimed at least 87 lives, have drawn strong condemnation from around the world.

UN Secretary-General Ban Ki-moon voiced his shock Friday over the attacks in Norway.

"The Secretary-General was shocked to learn about the large explosion in central Oslo and the shooting that took place in Utoya today. He condemns this violence and expresses his condolences to the Government of Norway and the families of the victims," the UN Chief said in a statement issued by his spokesperson.

"The United Nations stands together with the people of Norway at this terrible moment," he said.

UN General Assembly President Joseph Deiss also expressed shock and strongly condemned these attacks.

"President Deiss is particularly distressed that one of the attacks has targeted young people, and that this has happened on the eve of the High-Level Meeting on Youth convened by the General Assembly in New York on July 25 and 26, 2011 to mark the International Year of Youth," his spokesperson Jean-Victor Nkolo said.

Deiss also "strongly condemns these attacks and offers his condolences to the people and government of Norway."

In Washington, U.S. President Barack Obama on Friday sent condolences to Norway, calling on the world to work together to fight terrorism.

Obama pledged to provide support to the investigation and said the attacks were a reminder that the whole world has a "stake" in stopping this kind of terror from happening.

In Ottawa, Canadian Prime Minister Stephen Harper said he was "shocked and intensely saddened to learn of the attacks in Oslo and Utoya."

Condemning the terrorist activities, Harper said in a statement that he was also horrified to learn that a gunman opened fire at a youth camp at Utoya.

New Zealand Prime Minister John Key denounced the attacks as an act of global terrorism.

"I think it shows that no country is immune from that risk," Key said after a meeting with Obama at the White House on Friday.

In Copenhagen, Danish Prime Minister Lars Loekke Rasmussen expressed sympathy and solidarity with Norway and conveyed Denmark's readiness to assist in handling the situation.

"On behalf of Denmark and the Danish government I express my deepest condolences, sympathy and solidarity with the Norwegian people and the Norwegian government in this difficult time," said Rasmussen in a press statement.

In Bucharest, the Romanian Foreign Ministry strongly condemned the attacks and expressed its full solidarity with the Norwegian government and people at this difficult moment.

In Latin America, Mexico, Brazil, Argentina, Costa Rica and El Salvador sent condolences to the victims of the attacks and expressed solidarity with Norway through various channels.

The twin attacks hit the northern European country on Friday. A bomb exploded in downtown Oslo near government offices, killing 7 people and injuring more than 19 others. Hours later, a gunman dressed in police uniform opened fire at a youth camp of Norway's ruling political party on Utoeya, an island south of Oslo, killing at least 80 people.