Recording of prison conversation with lawyer shows former Egyptian president believes only solution to impasse is dialogue

Former Egyptian president Mohamed Morsi says the daily street protests by his allies since his removal last July are "useless", and that the man who toppled him – the army chief Abdel Fatah al-Sisi – may face the same fate if he succeeds him to the presidency.

In a leaked recording of a conversation with his lawyer in prison, Morsi agrees with his lawyer, former presidential candidate Salim al-Awa, that the only solution to Egypt's impasse is dialogue.

He suggests that Sisi, who took the decision to topple Morsi, will himself be deposed in a coup if, as expected, he becomes president this year.

Asked by Morsi for an update on Egyptian news, Awa describes and criticises the daily clashes between pro-Morsi protesters and security forces. Then he comments: "People must sit down, talk and reach a solution. Without reaching a solution, Dr Mohamed, there's no point."

Morsi agrees, and asks Awa rhetorically: "It's useless for both sides, no?"

Morsi's response may demoralise his rank-and-file supporters in the Muslim Brotherhood, who have consistently been told by their leaders that their daily street presence will eventually lead to Morsi's reinstatement. A total of 4,482 protesters have been killed at demonstrations and at least 16,687 Egyptians – most of them Morsi supporters – have been jailed for political reasons since his overthrow; and 198 security officials have been killed in attacks on police and army, according to figures from the Egyptian Centre of Economic and Social Rights.

Later in the conversation, Morsi expresses surprise that Sisi plans to run for the presidency, which is seen by many as a poisoned chalice. "He actually wants to be a president? … Isn't he afraid of a coup?" Morsi asks, before stating: "Whoever leads a coup must face a coup."

The conversation was leaked to a pro-regime newspaper this week. A member of Morsi's legal team has confirmed to the Guardian the veracity of the recordings, but condemned them as a crime that infringed Morsi's rights to a fair trial.

Morsi is in jail near Alexandria, Egypt's second city. He faces four separate trials on charges ranging from incitement to violence, terrorist conspiracy, espionage and insulting Egypt's judiciary. His allies say the charges are politicised.

Additional reporting by Manu Abdo