"On the telephone tapping issue. Several leaders, including Congress Legislature Party leader Siddaramaiah, have said it should be probed and truth should come out, so I have decided to order a CBI probe. Tomorrow itself I will order the probe," Yediyurappa told reporters here.
He also said it was the expectation of the people of the state that a detailed inquiry should be made and the culprits punished.
Yediyurappa's announcement comes amid signs that the scandal is gaining political steam ever since disqualified JDS MLA A H Vishwanath, who served as the JDS state president and turned rebel later, last week dropped the political bomb, accusing the H D Kumarswamy government of tapping phones and spying on more than 300 leaders, including him.
Congress leaders, including Siddaramaiah, M Mallikarjuna Kharge and home minister in the alliance government M B Patil, have sought a probe while another key party leader and former minister D K Shivakumar has rejected the snooping charges and appeared to side with Kumaraswamy.
According to reports, phones of those close to Siddaramaiah, who was the then coalition coordination committee chief, had come under the watch of the government.
Vishwanath had also claimed snooping would not have happened without the knowledge of the then Chief Minister as the intelligence wing was under his control.
Several BJP leaders, including former chief minister Jagadish Shettar, have directly accused Kumaraswamy of being behind the episode to save his government which was then rocked by dissidence within.
The coalition government ultimately collapsed last month with the chief minister losing the trust vote in the assembly.
Kumaraswamy on his part has denied the allegations.
"There was no need for me to remain in and save the chair (of CM) by tapping phones. Allegations made against me by some people in this matter is far from truth," he had tweeted.
The controversy surfaced as Bengaluru police commissioner Bhaskar Rao earlier this month ordered an inquiry into phone tapping incident against the backdrop of a recently leaked telephone conversation purportedly between him and someone in Delhi lobbying on his behalf with some politicians for the post he is occupying now.