After spending Friday morning holding short talks with the leaders of the Moderate, Liberal and Centre parties, he emerged smiling and gave a press conference to the Swedish media.
"There are good prospects for co-operation with the alliance parties", he told reporters.
He was scheduled to meet with Christian Democrat leader Göran Hägglund later in the day.
Sweden's future has remained unclear since Sunday's election. Prime Minister Fredrik Reinfeldt conceded defeat for his Moderate Party-led coalition government.
The Social Democrats won the biggest share of the vote (31.2 percent) but were left needing support from other parties.
The party's leader Stefan Löfven has confirmed that he will work with the Greens and indicated that he would be willing to work with the Liberal and Centre parties.
Earlier on Friday, Annie Lööf confirmed that the Centre Party did not want to join a Social Democrat coalition.
But Löfven's latest comments suggest that there will be co-operation on some Alliance policies that his party backed while in opposition, including those linked to immigration and free schools.
"We will continue partisan understandings reached," said Löfven.
Centre Party leader Annie Lööf says she won't enter a formal coalition agreement with the Social Democrats. Photo: TT
But Stefan Löfven is still likely to face opposition party's budget proposal, which is expected in the next fortnight.
Earlier on Friday, Centre Party leader Annie Lööf confirmed that she was working with the other groups that made up the previous Moderate-led Alliance to put forward a rival budget.
"For his budget, Stefan Löfven must seek support from the Green Party and the Left Party," she told news agency TT.
There have been fears that a fresh election could be called if the Alliance budget gets more support in parliament than the one put forward by the Social Democrats, although political analysts have told The Local that this scenario is "unlikely".
There were signs on Friday that patience with Lööf's tough stance might be wearing thin within parts of the Centre Party. Former leader Olof Johansson, who supported Ingvar Carlsson's Social Democratic government in the 1990s, criticized the Centre and Liberal parties for not being "constructive."
"Constructive opposition was the word I used. I said that we won't run and hide. The Centre Party and I have always been of the view that you have a duty to think of what's best for the country," he told Dagens Industri.