After an election that produced no clear winner, the country is currently being run by a caretaker government of the centre-left.
Officially, this kind of government cannot make any radical or partisan decisions, which would ordinarily include the budget proposal. Instead, they have put forward a budget intended to be as politically neutral as possible, and the finance minister has agreed with the opposition Alliance and the Left Party about certain principles.
Opposition parties can also put forward their own budget proposals, and several have said they plan to do so.
The Moderates and Christian Democrats will put forward a proposal, without the other two parties that make up the centre-right Alliance (the Centre Party and the Liberals).
Meanwhile, the Centre Party will also put forward a budget proposal, and has said it will vote for its own and abstain from the other votes.
The leader of the Liberals has said he is still not decided which, if any, budget proposals his party would vote for, and that this decision would be made on Tuesday.
Liberalernas diskussioner om ett mittensamarbete fortsätter. Vi har ännu inte tagit beslut om hur vi röstar i budgetomröstningen på onsdag eller hur vi röstar i en omröstning om Stefan Löfven som statsminister. Tanken är att partirådet i morgon ska avgöra.
— Jan Björklund (@bjorklundjan) December 10, 2018
The Liberals' discussions on collaboration in the middle continue. We have not yet decided how we will vote in Wednesday's budget vote or how we will vote in a vote on Stefan Löfven as prime minister. The idea is that the party council will decide tomorrow.
With support from the Liberals, the caretaker government's budget could be passed; otherwise, the centre-right proposal from the Moderates and Christian Democrats looks likely to win the vote.
A defeat for the caretaker government's budget would be a blow for Social Democrat leader Stefan Löfven, who is the latest leader tasked by the parliamentary speaker with trying to form a government that can pass a parliamentary vote.
If he succeeds in passing the parliamentary vote, but the budget proposed by the Moderates and Christian Democrats also passes, the Social Democrat leader would face a dilemma. A similar situation occurred in 2014 after Löfven was voted in as PM but the opposition's budget was voted through.
This prompted Löfven to call a snap election, which was only cancelled after the parties agreed on a controversial deal, the 'December agreement', in which the opposition agreed not to vote on its own budget, therefore allowing minority governments to govern. That agreement was called off a few months later, however, so if the same situation arises again, the party leaders will have to think of a new resolution.
As things stand, it is unlikely that Löfven will pass a parliamentary vote to become PM, after the Centre Party said it would not support his candidature.