Opposition Leader Wan Azizah Wan Ismail has to "stay above" the signing of a declaration today where unlikely allies have agreed to work together to remove Prime Minister Najib Abdul Razak.
This is why she did not attend the press conference where former prime minister Dr Mahathir Mohamad has signed a declaration with various opposition figures, said PKR secretary-general Rafizi Ramli.
"For Wan Azizah, it is the political bureau's decision that she stays above this and helms from Pakatan Harapan's presidential council.
"(This is) because it is very important that she remains firm on the reform agenda we have agreed that Pakatan Harapan will spearhead," he told Malaysiakini in a series of text messages.
This way, he said, they can ensure that the momentum built by Pakatan Harapan so far is not so easily "hijacked".
It is fine for individual opposition figures to commit to this declaration, he added, but they are subjected to the direction set by Pakatan Harapan.
"This is a good way to ensure check and balance. So it is important that Wan Azizah stays above this and commands Pakatan Harapan from the presidential council.
"That's why the presidential council will make its announcement of (Pakatan Harapan's) next steps on March 7," he said.
On Monday, Mahathir had announced that he was quitting Umno to protest Najib's leadership, and he expressed an interest in forming a core group to work towards the goal of removing Najib.
Despite Pakatan Harapan distancing itself from today's declaration signing, several of its top leaders attended today's press conference, including DAP veteran Lim Kit Siang, PKR vice-president Tian Chua, and Amanah president Mohamad Sabu.
Pakatan Harapan had previously clarified that if any of its leaders attended the press conference, it would be in their own personal capacity.
PAS has refused to endorse the declaration but several prominent PAS figures have also attended, such as Mahfuz Omar and Mustafa Ali.
In a statement yesterday, Anwar, who is serving a five-year prison term, also expressed support for the initiative, despite his previous accusations that Mahathir had fabricated charges against him.