Eighteen ministers were sworn into office in Nepal Wednesday after the prime minister forged a new communist coalition by sacking old allies, the latest shakeup in Kathmandu's volatile parliament.

Prime Minister Pushpa Kamal Dahal, 69, an ex-Maoist guerrilla better known by his nom de guerre Prachanda or "the fierce one", leads the Maoist Centre party, the third largest in the 275-member parliament.

He fell out with his former partners, the centrist Nepali Congress (NC), and the largest party in parliament. They now form the opposition.

Dahal has instead rebuilt an alliance with the Communist Party Nepal-Unified Marxist Leninist (CPN-UML), led by former prime minister K.P. Sharma Oli, viewed as being pro-China.

"Eighteen new ministers from four parties are taking their oath... and will assume their office," said Govinda Acharya, the prime minister's press advisor.

Nepal, a Himalayan nation of 30 million people, is sandwiched between powerful neighbours India and China -- with both New Delhi and Beijing campaigning for influence.

Kathmandu has sought to balance ties while boosting its economy.

The ministers were sworn into office by President Ram Chandra Poudel, with Maoist ministers Narayan Kaji Shrestha and Barsha Man Pun taking the foreign minister post and the finance minister post respectively.

Three ministers were sworn in on Monday.

The Maoists have dominated Nepal's politics for more than 20 years after waging a decade-long insurgency against government forces that claimed more than 16,000 lives.

The civil war ended in a 2006 peace deal, which saw rebel leader Dahal become Nepal's first post-war prime minister.

The three main parties -- the Maoists, CPN-UML, and the NC -- have since monopolised politics, forming varying brittle coalitions with one another.

Dahal allied with the Nepali Congress after the general election in 2022, following a rift with the CPN-UML over a presidential candidate. But he later switched his alliance back to the CPN-UML after facing difficulties working with the NC.