Oil-rich Gulf state Kuwait is embroiled in an unprecedented constitutional crisis pitting two branches of the ruling Sabah family against each other.
The ruling family split has gripped Kuwaitis
The cabinet has asked parliament to support the removal of Emir Sheikh Saad al-Abdullah on health grounds.
Supporters of the sheikh have responded by asking for his swearing-in to be held before MPs can convene.
But the move was rejected by the speaker, and parliament will decide the emir's fate in a vote on Tuesday.
Constitutionally, when requested by the cabinet, Kuwait's parliament must vote by a two-thirds majority for an ailing emir to be removed.
If the new emir is voted out of office, it would be the first time a Kuwaiti ruler is removed by parliament.
Sheikh Saad, 76, has played little part in public life for several years, despite being crown prince to Emir Sheikh Jaber, who also suffered poor health.
Affairs of state have been controlled by his cousin, Prime Minister Sheikh Sabah al-Ahmad, who is the half-brother of the late emir.
Observers say he is expected to take power in the event of Sheikh Saad's removal from office.
Tradition in the Sabah ruling dynasty stipulates that the position of emir should alternate between the two main branches of the family.
These are the Jaber branch, of which Sheikh Sabah and the late emir are members, and the Salem branch which produced Sheikh Saad.
Sheikh Sabah has in effect been running the country for years
The public conflict between the two branches over the succession has stunned the normally tranquil circles of Kuwaiti politics.
Parliament received a letter from the cabinet early on Monday which claimed the emir has "lost his health capability to exercise his constitutional prerogatives".
Hours later, MPs said they had received a letter from Sheikh Saad "which includes an order to hold a session to take the oath this evening".
Parliament speaker Jassem al-Khorafi "refused the demand", Muhammad Sager MP told reporters.
Sheikh Saad's supporters have been putting up posters across the emirate hailing him as a "hero of the liberation of Kuwait" in reference to the 1990-91 Gulf Crisis.
The sheikh appeared only briefly during condolences for Sheikh Jaber last week. He was in a wheelchair to receive handshakes and kisses on the shoulder from mourners.
Parliament has 50 elected seats, including 15 members of cabinet, which is dominated by the Sabah family and supporters of Sheikh Sabah.
The emirate controls about 10% of the world's proven oil reserves and is a key US ally in the region.