General Motors have taken the decision to start official proceedings to wind down the Saab Automobile in Trollhättan.
GM said hired the consulting firm AlixPartners "to supervise the orderly wind-down of Saab, and has requested approval of the selection by the appropriate authority in Sweden".
The US auto giant, in the process of a massive restructuring after bankruptcy last year, said the process for Saab "is expected to take several months, and will ensure that employees, dealers and suppliers are adequately protected".
The union, which has a representative on Saab's board, criticised GM for taking such a step at the same time that it had confirmed having received several bids for the iconic Swedish brand.
"It is irresponsible of GM as an owner to go in two directions, both pursuing the sale (of Saab) and the winding up," Löfven said.
Several groups, including sportscar maker Spyker and a group comprised of boss and a Luxembourg investment firm, have said they presented GM with last-ditch bids to rescue Saab.
"It is unintelligible and irresponsible to do that now without reviewing the serious bids that have been placed for Saab," Löfven said.
"GM's decision is not in line with the signals we have received from the company about its sincere intentions of wanting to sell Saab and seriously reviewing incoming bids," he added.
"Essentially, the two processes will continue in parallel, which means we'll continue with a (winding up) and at the same time we will look at the proposals and analyse them and see whether we can find a good solution for everybody," Weinmann said.
GM's actions regarding the Saab sale, which it put on the a year ago, have been repeatedly denounced by the Swedish government and Saab's unions.
"We will see what we can do, in order to, if possible, contribute to a positive sale of Saab," Jöran Hägglund, Swedish enterprise ministry state secretary, told Swedish news agency TT on Friday.
He will be heading a Swedish delegation travelling to Detroit on Saturday to hold talks early next week with officials from GM and , which is in the process of selling its Swedish unit to Chinese carmaker Geely.
Analysts have warned that some 8,000 jobs could be lost with Saab's closure.
Saab's board met on Friday in the carmaker's hometown of Trollhättan. A GM source told AFP on Thursday that the closing of the operation was on the meeting's agenda.