A royally sponsored bathing ceremony for the late former prime minister Banharn Silpa-archa will take place at Wat Thep Sirintharawat in Bangkok at 6pm on Saturday.
Privy Council president and statesman Gen Prem Tinsulanonda will bring the royally bestowed bathing water and stay on for the prayer ceremony to be held later.
The first seven days of praying will be royally sponsored while relatives will host the ceremony over the next seven days.
Banharn, an 11-time Suphan Buri MP, passed away at Siriraj Hospital on Saturday morning after suffering an asthma attack and having difficulty breathing.
PM Gen Prayut Chan-co-cha said his death was a loss and he would be remembered.
"The prime minister expressed condolences to the Silpa-archa family and to those who respect him. He believes what Mr Banharn had done as an MP and prime minister will be forever remembered," Maj Gen Sansern Kaewkamneard, spokesman of the Prime Minister's Office, said on Saturday.
Former prime minister Yingluck Shinawatra expressed condolences on Facebook on Saturday morning.
"I heard the news about Mr Banharn's passing this morning and I feel it's a great loss.
"Having known him for so many years, I found him to be a well-respected and down-to-earth puyai to all. When I visited Suphan Buri, he took me to Bueng Chawak [a fresh-water lake and aquarium], and other major attractions in the provinces by himself," she wrote.
"Throughout his political career, whether as an MP or prime minister, he was determined and dedicated to looking after the people and developing each area.
"He is well respected by members of not only his party but also other parties," she wrote.
In his hometown Suphan Buri, the province prepared four places for people to sign and express condolences starting at noon on Saturday, said deputy governor Veerasak Vichitsaengsri.
Prasit Wattanapa, dean of Mahidol University's Faculty of Medicine, Siriraj Hospital, said Banharn was admitted to the hospital in the early hours of Thursday. He died peacefully at 4.42am. He was 83 years and eight months old.
Banharn suffered an asthma attack at 3am and relatives applied an inhaler to help him breathe. After the symptoms did not improve, they took him to the hospital.
"On his way here, the body already lacked oxygen and we put him in intensive care unit. We gave him medication to help him breathe and for heart disease, as well as oxygen," Dr Prasit said.
He died two days later due to lack of oxygen and breathing difficulties after becoming increasingly less responsive to medication.