The call was made as the special 12-member committee created by Parliament to consider the president's reply sat for the first time on Thursday.
"I don't see why anybody would not want to come and respond to the allegations against them," Democratic Alliance parliamentary leader Lindiwe Mazibuko said.
"We hope people will be willing to accept an invitation, but this committee has the legal power to subpoena anybody."
The committee is chaired by National Assembly house chairperson Cedric Frolick and is due to finish its work by 30 April.
It will only reconvene on Monday, making an exhaustive inquiry into Madonsela's findings regarding the R260m spent on improvements at the president's home in Nkandla unlikely.