Støre was the keynote speaker at the May 1st event, which is held annually in support of workers' rights and to highlight important issues for workers.
“One of the first things the Labour Party will do in government will be to forbid these ludicrous contracts by law,” Støre said in his speech at Oslo's Youngstorget plaza, referring to a 2015 law change by Prime Minister Erna Solberg's Liberal (Høyre) Party government allowing non-permanent employment contracts.
“We must fight social dumping and degrading employment contracts. Some people call it modern working life, but it is not new. We used to call it casual labour society. And we do not want to go back to that,” Støre said, according to a report by broadcaster NRK.
Social dumping is a term usually to describe the practice of employers taking advantage of cheaper labour by moving their base of production.
But other left-of-centre parties do not share all of Labour's positions in the area of employment, according to motions at the party's recent congress, reports NRK.
These include stricter measures on social welfare, with Labour not wanting to forbid profit-making kindergartens; and pulling out of the EEA, which Labour does not support, saying the current agreement is beneficial for Norway.
Støre, who gave the keynote speech at the May 1st event, underlined what he said was a clear choice in Norway's September general election: a continuation of the current Liberal-led coalition government, which also includes the anti-immigration Progress Party (Fremskrittspartiet), or a new Labour-led government.
“It is down to the right-wing parties, who have weakened employment rights conditions and forced workers into the biggest general strike since the war, and us, who aim to strengthen and improve employment rights laws,” he said according to NRK's report.
Støre also said that the fight for equal rights at work would be a big part of this year's election campaign.
“This election will be about how we build on the best of Norway. Small differences. Work for everyone. Creating and sharing. Showing our solidarity with people in the world that need help. And that we in this country never give up until we have taken care of each other,” he said.
“Together we will win the election,” Støre said, rounding off his speech.