"Many don't have any idea about how their fellow humans are living just a few bus stops away. It's dangerous, very dangerous for our society," he said during a speech delivered to some 500 of his party's local and regional politicians.
The prime minister also voiced concerns about increasing segregation between schools and between neighborhoods and that that means there are too few natural opportunities for people who come from different backgrounds and classes to meet.
He claimed that Sweden has been drifting apart for the last decades and that people's ignorance about each other is being exploited by both right-wing extremists and by violent Islamists, in order to advance their own agendas.
Löfven said that holding Sweden together means developing the Swedish model.
"The Swedish model is in our hands," he said.
According to Löfven, the Swedish model is founded on three critical parts: 1.) that everyone works, which he says requires investments in education and infrastructure, to allow people and companies to succeed in the world economy, 2.) that resources are apportioned fairly so that profits do not just wind up in the hands of a few but, he says, contribute to the well-being of all, and 3.) that there is a secure welfare system.
He said that in budget talks with the Greens and the Left party, employing more people within the welfare sector will be a priority.
"It's important that municipalities and county councils have good conditions for planning," said Löfven.
"And our message to Sweden's welfare workers is: You shall not have lower salaries, rather more colleagues," Löfven continued, but he did not specify any numbers.