A meeting of the Cabinet took the decision earlier in the day based on the recommendation of the Election Commission.
As per the recommendation, the elections are being held on the same days in an effort to make it cost-effective and easier for the poll body to manage.
With the announcement of the polls, the Sher Bahadur Deuba-led coalition government has now turned into a caretaker one and cannot take crucial decisions.
The Election Commission now has 107 days to prepare for the polls, which the Chief Election Commissioner says is enough time.
As per the Election Commission Act 2017, the government announces election dates in consultation with the Election Commission.
The election date was earlier recommended for November 18, according to officials of the polls body, assuming that the tenure of the existing House of Representatives and Provincial Assembly would end on December 8.
The Commission had declared the early winners of the second phase of the elections in federal and provincial elections in 2017 on December 8 under the first-past-the-post system.
The previous federal and provincial polls were held in two phases on November 26 and December 7 in 2017.
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