A split within Nepal's communist-dominated ruling coalition plunged the Himalayan nation into crisis on Monday.
It is due to appoint its next president on March 9.
Nepal has had 11 governments since it abolished its 239-year-old monarchy in 2008 and became a republic.
Mr. Prachanda angered the UML by endorsing the opposition Nepali Congress Party's presidential candidate Ram Chandra Paudel.
Nepal is moving towards new instability