"It is true we are interested in Thiago and we are in talks with him. Nothing is closed, the player has not said yes. If he comes, it will be on the terms we want, we do not have an oil well to spend money that does not exist. We are working on it, but there is no agreement," Boto told Paparazzo Rubro-Negro.
Despite acknowledging other clubs remain interested in the Argentina international, Boto said he was confident the move could still be completed.
Flamengo already have a verbal agreement with Almada's representatives, according to Brazilian outlet Ge, and are now working to finalise the details with Atletico Madrid, who hold 50 per cent of the player's economic rights, with Botafogo owning the remainder.
Flamengo's expected offer is understood to exceed the roughly €20 million bid already submitted by River Plate, though it is likely to remain below the €28 million Atlético are seeking. Almada, who has no space in Diego Simeone's starting line-up, has already turned down approaches from Russian and Saudi Arabian clubs as he holds out for a return to South American football with Flamengo.
Boto also revealed that Flamengo are working on two further signings alongside the Almada deal.
"We are working on Almada and on two more players to reinforce the squad. It is not easy to improve this squad; people need to be patient so that we do not pay more than we should. Calmly, the players will arrive," he said.
Atlético originally paid Botafogo around €21 million for Almada's rights last year, a factor that has raised the price required for any onward sale. The two clubs have a strong recent working relationship, having previously completed the transfer of Samuel Lino to Flamengo for €22 million, and Flamengo are said to be banking on that history to help smooth negotiations.
River Plate's rival offer is seen as the greatest threat, both for the Argentine club's ability to match funds and the pull of a return home, though sources close to the Rio club say optimism remains high a deal can still be reached in the coming days.