Prime Minister Prayut Chan-o-cha on Thursday told military leaders that there is no rift between him and Deputy Prime Minister Prawit Wongsuwon.
Gen Prayut, also defence minister, insisted the rumour about him and Gen Prawit going through a rough patch was untrue.
Instead, the PM said he and Gen Prawit always had a healthy relationship.
The issue was raised during the last Defence Council meeting of the 2021 fiscal year, which was attended by leaders of the three armed forces and other high-ranking officers.
Reports of tensions between the pair emerged following the sacking of Thamanat Prompow and Narumon Pinyosinwat, Gen Prawit's close aides, from the cabinet. Gen Prawit was reportedly kept in the dark.
"There is no rift between me and brother Pom [Gen Prawit]. There is only love between us and it will stay forever that way. Nothing will come between us," Gen Prayut was quoted as telling the leaders of the armed forces during the meeting.
Gen Prawit, who serves as adviser to the Defence Council, did not attend the meeting.
The rift speculation was fuelled again earlier this week when Gen Prayut and Gen Prawit made separate flood inspection trips on the same day.
Lt Gen Kongcheep Tantravanich, spokesman for the Defence Ministry, on Thursday also dismissed the rumour about tensions between Gen Prawit, Gen Prayut and Interior Minister Anupong Paojinda.
He also played down the separate inspection trips held on Wednesday, saying they were to gather details of local people's needs for cabinet consideration. Gen Anupong was seen accompanying Gen Prayut in Phetchaburi while Gen Prawit was escorted by cabinet ministers and MPs from the Palang Pracharath Party.
According to Lt Gen Kongcheep, the prime minister also emphasised unity and assured that the coalition government was on the same team.
Meanwhile, Gen Prawit, also leader of the PPRP, did not join the party meeting and had Capt Thamanat, the party's secretary-general, preside over the session.