"I have directed the Chief Minister to hold the floor test in the Assembly on Thursday (July 18)," Speaker K.R. Ramesh Kumar told reporters after a meeting of the Business Advisory Committee of the House here on Monday.
The meeting was attended by Kumarswamy, Congress Legislature Party leader Siddaramaiah and opposition BJP leader B.S. Yeddyurappa.
The floor test will be held at 11 a.m. on Thursday.
The BJP has been demanding the floor test in the wake of resignation by 16 MLAs of the ruling alliance 13 of the Congress and 3 of the JD(S) and withdrawal of support to the Kumaraswamy government by two other legislators.
The resignations have not yet been accepted by the Speaker, who has said he would need time to study whether these were in proper format.
Unhappy with the delay by the Speaker in accepting their resignations, 15 of the rebel MLAs have moved the Supreme Court, apprehending that they could be disqualified.
The top court on July 12 ordered a status quo on the petitions till Tuesday when the matter would be heard again.
The Congress-JD(S), along with lone legislators each of BSP and a regional party and an Independent, have 118 MLAs, including the Speaker, in the 225-member House.
If all the 18 legislators, including 16 rebels and 2 Independents do not attend the session, the effective strength of the House for voting will be 205, including 105 of the BJP and excluding the Speaker and the nominated member.
"As the new halfway mark will be 103 for a simple majority, the ruling combine with 100, including one from the supporting party BSP will fall 3 short off it (halfway mark) to win the trust vote and certain to be defeated," according to BJP spokesman G. Madhusudana.
( With inputs from IANS )