"It was decided that the committee wishes to continue discussions, we accepted that," he told a press conference after the board met in Yokohama.
Media reports ahead of the meeting suggested the board was unlikely to reach a decision soon, in part because of open discord with French automaker Renault.
Nissan itself faces charges of allegedly submitting financial documents that understated Ghosn's pay, and Renault is now reportedly seeking more sway on the Japanese firm's board.
The French firm has reportedly urged Nissan to call a shareholder meeting to discuss its representation on the board and within its top management.
It warned Nissan's indictment "creates significant risks to Renault, as Nissan's largest shareholder, and to the stability of our industrial alliance", the Wall Street Journal reported.
Saikawa declined to comment directly on the reports, and said Nissan would look to organise a shareholder meeting after a panel examining governance at the automaker reported its findings.
In a statement, Nissan said it was ready "at any time to provide a full briefing at a Renault board meeting in order to maintain an equal understanding among the Alliance partners".
But Saikawa's comments also made it clear that relations between the partners are increasingly difficult.
"We have approached Renault. But the reaction of the Renault board was to refer us to their lawyers. So now Nissan's lawyers are communicating with Renault's lawyers," he said.
"My understanding is that the graphic details of the wrongdoing is not being conveyed to each and every one of the Renault board members. If we are afforded such an opportunity, we would very much like to explain."
Ghosn's arrest has laid bare the rifts in the alliance between Nissan, Renault and Mitsubishi Motors that the auto tycoon helped forge -- and was often credited with holding together.
While Nissan and Mitsubishi Motors quickly removed Ghosn from leadership positions after his arrest, Renault has kept him on as CEO and chairman.
And while Saikawa launched a broadside against his former mentor shortly after his arrest, describing his "dark side", Renault has approached the allegations more cautiously.
The CEO said he would not rush the three-person panel advising the board on the new chairman.
I don't have any deadline in mind. I wish them to spend all the time they need," he said.
A newly formed committee looking into governance at Nissan is to report its findings by March, but the decision on a new chairman could potentially stretch beyond that, he said.
As his former employer wrangles over his replacement, Ghosn remains in the one-man cell at a Tokyo detention centre he has occupied since his shock arrest on November 19.
Prosecutors have already charged him with under-reporting his pay by around $44 million over the five years to 2015, and are also investigating claims he under-reported it further in the past three years.
He will be detained until at least December 20, when prosecutors will either file new charges or request another 10-day detention period while they continue investigations.
A range of additional claims of financial misconduct have been made against Ghosn, including using Nissan funds to purchase homes around the world, though prosecutors have yet to level those accusations formally.
He and his former right-hand man Greg Kelly, who is also under arrest, reportedly deny any wrongdoing.
The charges have sparked a legal battle over Ghosn's flat in Rio de Janeiro, with Nissan trying to prevent his family members from accessing the property and removing items.
A Brazilian court authorised relatives to access the apartment, despite claims from Nissan that they were removing corporate documents.