The news conference held at the Transcorp Hilton Hotel, Abuja.
Mr Atiku has been advocating for coalition talks with other opposition leaders in the country.
The former vice president arrived at the Olusegun Obasanjo Presidential Library in Abeokuta at 12:36 p.m.
The tribunal will hear Mr Abubakar and the PDP’s motions seeking live transmission of court proceedings and petitions challenging the presidential poll’s outcome.
“If we make another mistake, it will be the end for Nigeria,” stated the former Cross River governor.
The 326-member PDP Presidential Election Campaign Council will be inaugurated on September 28.
The former vice president said as president he would give more powers to the state and local government councils.
“We have never lost an election in Cross River since 1999 when Nigeria returned to democracy; a defection is not a loss.”
“Where they are, we know, they are not happy… Kindly reach out to them and bring them back home,” Mr Ayu said.
The Sokoto governor said “Nigeria must restructure its polity, economy, security and ways of doing things.”
