Okayed by the cabinet, the budget contains many social measures and a rise in investment in Catalonia, whose regional government wants independence but whose lawmakers in the national parliament are crucial for Prime Minister Pedro Sanchez's minority government.
“This budget is good for Catalonia and therefore those who defend Catalonia should approve it,” Budget Minister Maria Jesus Montero told reporters, in reference to lawmakers from the northeastern region.
“The (Catalan) government is constantly asking for more resources for Catalonia, and it has an opportunity in this budget.”
The lower house will start examining the draft budget on Monday.
Sanchez's Socialists only have 84 lawmakers out of 350 and need the support of a far-left coalition led by Podemos — 67 seats — as well as other lawmakers, the most crucial being the 17 Catalan separatists.
These backed Sanchez's no-confidence motion against his conservative predecessor Mariano Rajoy in June, thereby helping topple and replace him.
That has earned Sanchez, who has pledged to keep going until the next general elections in 2020, furious criticism that he is cuddling up to Catalonia's separatists.
This time round, though, Catalan lawmakers may not be so accommodating as the mega-trial of separatist leaders who participated in the October 2017 attempt to break from Spain looms.
If they don't vote for the budget, Sanchez's government will likely fall.