Parliamentary speaker Andreas Norlén decided on Tuesday to extend Andersson’s deadline until Monday.

“I was informed that there’s progress but more time is needed. I want Sweden to urgently get a new government, but at the same time the work should not be forced,” said Norlén in a statement after meeting with Andersson on Tuesday morning.

Under Sweden’s system of negative parliamentarianism, a prime ministerial candidate needs only to convince a majority of members of parliament not to vote against them. But with the slim margins in the Swedish parliament, that is not a safe guarantee.

Andersson needs either the votes or the abstentions of the Left Party’s 28 MPs – which she has not yet secured. Together with the government’s 100 Social Democrat MPs and 16 Green Party MPs, and the Centre Party’s 31 MPs, this will bring her to the magic majority of 175 mandates (the right-wing parties have 174 seats in parliament).

The Left Party has made being brought back into negotiations its main demand for supporting (usually described as “tolerating” in Sweden, since abstaining is enough to let a candidate through) Andersson as the new prime minister, so one factor is the outcome of those talks.

Andersson said on Tuesday that “constructive talks” with the Left Party were ongoing and that she was “prepared to make some concessions”, although the TT newswire reported that she would not be drawn on what issues she would consider compromising on.

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Left Party leader Nooshi Dadgostar has previously mentioned higher pensions and scrapping Sweden’s unpaid first day of sick leave (karensdag) as two policy changes she would like to see, but she has also indicated that she would be willing to compromise.

Before the firm Monday deadline, Andersson is set to give Norlén an update on how negotiations are progressing by Friday.

If Norlén wants to, he will be able to propose Andersson as a candidate to parliament on November 24th at the earliest. He can do this either if he thinks her government has a good chance of being accepted, or even if he thinks it doesn’t, just to move the process on. He can also decide to give her more time to conclude negotiations, or hand the job of trying to form a government over to another party leader.