He had until midnight tonight to find fresh backing in parliament, enabling him to hand over the job of finding a new government to the speaker with the expectation of being reappointed, or to call a snap election.
Lofven, a former union boss and welder, has headed a fragile minority coalition with the Greens since 2018, relying on support from two small center-right parties and the Left Party to remain in power.
The center-left and center-right blocs are now evenly balanced in parliament and opinion polls show a general election might not change the picture.
It took Lofven four months to form a government after 2018’s inconclusive election.