Membership of Norway's political parties has surged in response to calls to counter last week's massacre with more democracy and political participation, and some warn that the debate must shed traces of xenophobia.

All of Norway's main parties say they have seen a jump in membership since Norwegian Anders Behring Breivik killed 76 people last Friday in a bombing and shooting attack he saw as a "crusade" against Islam and multiculturalism.

An emotional Prime Minister Jens Stoltenberg has since then urged Norwegians to respond to the violence, in which Breivik gunned down youth members of his ruling Labor Party at a summer camp and planted a bomb outside Stoltenberg's offices, with more of what he says Norway does best -- openness and democracy.

"We have seen a jump in membership of all parties ... I think it shows that people are following what the prime minister asked for," Labor Party lawmaker Svein Hansen said, adding that the exact number of new members had not yet been counted.

The opposition Progress Party, whose strength has grown in recent years partly due to its tough line on immigrants, also said it had received a boost, gaining at least 487 new members.

"Usually it's very, very quiet at this time of the year, so this is something extraordinary. Normally in July most people are on vacation," said party spokesman Mazyar Keshvare.

"We know quite a bit about their motivation as well. In the internet application page, there's a comment box, and many, many people are saying 'I'm going to be more politically active so we can stay united against terror'," Keshvare said.

The Socialist Left party, in coalition government with the Labor Party, has seen members rise by at least 290 people, a large jump for small party and a country of only 4.8 million.

Norwegians are due to vote in local polls in September.

DEBATE MUST CHANGE

For some, more democracy and debate is not enough to combat what they see as rising prejudice against Muslims and immigrants in Norway and across Europe.

Some Norwegians see immigrants as exploiting the country's generous welfare and vast oil wealth; it has a sovereign wealth fund worth 3.1 trillion Norwegian crowns ($573.6 billion).

"It's a good call, but it's not enough. I don't know how we're going to take this debate forward. If you continue debating using generalizations and negative stereotypes, I feel that Muslims will be even more victimized than they are now," said the Norwegian Center against Racism's Mari Linloekken.

The Progress Party has fairly mainstream anti-immigrant views. It proposed this year that immigrants should receive lower welfare payments than Norwegian citizens.

However, a leaflet used in the 2005 election featured a gun and the caption "...the perpetrator was of foreign origin."

"We have never expressed such a thing that Muslims are taking over the country, or anything else like that, so I don't think that we have anything to be ashamed of or change when it comes to politics," Keshvare said.

"Problems surrounding this issue haven't changed because of this tragic event," he added.

Labour's Hansen said he hoped rhetoric would be toned down.

"One of the things I hope that we will draw as a lesson from this is that we have to talk about immigration, integration, Muslims and so on in another language .... We have to change language to one more in line with reality," he said.

Norway has lower levels of immigration than most other Western countries.

For Tunisian-born Norwegian Izzeddine al-Saweih, 57, change will not come soon enough.

"There has to be a debate on the right principles, an open debate, and Muslims must take part," he shouted at an outdoor gathering of Labor Party politicians in Oslo Thursday.

"The media writes a lot negative things about us, big and small. They put us under suspicion, and now we don't know our identity, despite us belonging to this land and its laws. Why?"