Kulanu leader Moshe Kahlon warned Prime Minister Benjamin Netanyahu and Blue and White leader Benny Gantz on Saturday night that if he would not receive the Finance portfolio, he would not join the government.
Kahlon made the threat, even though Kulanu is expected to fall from its current 10 seats to four or five, according to the polls.
Zehut leader Moshe Feiglin, whose party is beating Kulanu in the polls, has demanded the portfolio for economist Gilad Alper, who is third on his list.
In an interview with Channel 12 on Saturday, Netanyahu vowed to lower taxes if re-elected on Tuesday.