"It is a serious failure of Social Democracy and of our party leader. The confidence in Håkan Juholt was down to a catastrophic 16 percent shortly before Christmas. Our awful position and low trust cannot be blamed on anyone else."
Ex-minister Johansson wrote on her blog that the former giant Swedish political party now seems to be stuck at 25 percent of voter support, which she is not satisfied with.
"It is the party itself and our leader who have messed up," she added.
However, despite the stinging criticism Johansson doesn't wish to see Juholt step down.
Maintaining that she believes Juholt has failed in his task, she said that it is now up to him and the party to make it right again.
The object of writing in the blog was to highlight how this is a problem for the party to solve together, that the blame can't be passed on to someone else, she told news agency TT.
"This is a very serious situation. Month after month we get historically low results in polls both for the party and for the party leader," she said.
"What I want to say in the blog is that we can't blame this on anyone else and that it is in our own hands."
Despite the harsh words, Johansson claims she still has faith in Juholt, and that she simply wishes he is able to turn the situation around.
"I hope so," she told TT.