The Nepali Communist Party (NCP) has also withdrawn from the Madhesh provincial government as political parties continue exploring new alliances to form a government in the province.
The NCP has recalled its four ministers, ending its cooperation with the government led by Nepali Congress leader Krishna Prasad Yadav.
Following the NCP's decision, the provincial government led by Chief Minister Yadav is in deeper crisis.
Yadav, who is required to seek a vote of confidence within a week, is now facing an even greater political challenge.
Earlier, the CPN-UML, which was also part of the government, recalled its ministers on October 16. After the UML's exit, the NC-led government had remained in power with the NCP's support. Now, the NCP has also withdrawn its backing.
NCP parliamentary party leader and Finance Minister Yuvaraj Bhattarai said that the party decided to leave the government to help end the political deadlock in the province.
"This government is unlikely to continue. A new political alliance has also not yet been formed. We have stepped aside to pave the way for a political resolution. We have submitted our resignations," he told Setopati.
Following a directive from party chief Pushpa Kamal Dahal, a virtual meeting of the NCP parliamentary party decided to withdraw from the government. Accordingly, four ministers, including Bhattarai, tendered their resignations.
Those who resigned include Bhattarai, Minister for Industry and Tourism Kanish Patel; Minister for Home Affairs, Communications, and Law Fakira Mahato; and Minister for Energy, Irrigation, and Water Supply Jawahar Kushwaha.
The issue of a possible change in government in Madhesh province has recently prompted political parties to explore new alliances.
Following the UML's withdrawal, the NC-led government had been under pressure to secure the support needed to remain in power. However, as efforts to resolve the political deadlock continued, the NCP also decided to leave the government.