"A SCRIBBLED note that has caught fire in PKR" - that was how one PKR politician described the impact of Datuk Seri Anwar Ibrahim's letter from prison.
The eight-page missive, penned in Anwar's neat and rounded handwriting, zeroed in on Dr Mahathir, criticised the former premier's dominance in the Citizens' Declaration and questioned the elder man's motives.
If one had to summarise what the letter was about, it would be that Anwar is pulling the brakes on his party's involvement with his old nemesis.
Anwar's letter has been the subject of fierce debate in PKR circles.
The man whom PKR knows as ketua umum or paramount leader, had initially extended support for the Citizens' Declaration, but it is apparent he has had a change of heart.
He is now cautioning his party against getting too involved with what he sees as a flawed agenda set by "a former autocrat" and which is not consistent with his ideas of reform and democratic change.
His view is that Dr Mahathir does not have reform in mind but only wants to remove Datuk Seri Najib Tun Razak as Prime Minister.
He said he was dumbfounded by the simplistic argument that all problems will be solved by removing Najib and that it will lead to democratic changes.
Although written in that civil Malay manner of saying things, the letter was a strong missive of his misgivings about the campaign since its launch in March.
He is basically saying that the Citizens' Declaration is not for him and that the party should not be carried away by Dr Mahathir.
He is still deeply distrustful of Dr Mahathir, he has not forgiven the older man for what he has done and he certainly does not believe Dr Mahathir is the best person to lead a campaign for political reform.
Although his words were meant largely for his party, it was also aimed at the leaders of Pakatan Harapan.
Word has got back to him of how leaders like the Lim father-and-son as well as PKR leaders had appeared to be dancing around Dr Mahathir.
Read also: Dr M urges public to sign declaration to voice discontent
He warned them not to be taken in by political trickery and reminded them of how they had been played out in the statutory declarations plot allegedly initiated by Tengku Razaleigh Hamzah.
"Anwar is upset that the whole thing is not reform-oriented enough. The Pakatan Harapan presidential council did decide earlier on that although we support the Citizens' Declaration, we should do it our way. Anwar is not happy that things are being done the Mahathir way," said the coalition's chief secretary Datuk Saifuddin Abdullah.
Anwar did not pull his punches on how he felt about Dr Mahathir, whom he referred to as "a cruel leader" who has shown no remorse for his past deeds or support for reform.
He referred to Dr Mahathir and Tun Daim Zainuddin as the "architect and aggressive exponent of crony capitalism".
PKR insiders said that Anwar's letter was triggered by the announcement that the campaign has amassed 1.2 million signatures and that he is fearful of his continued relevancy.
There are also suggestions that Anwar was infuriated by an interview Dr Mahathir gave to an Australian newspaper.
Dr Mahathir was reported as saying that Anwar was not fit to lead the country because of his "immoral behaviour". He also downplayed Anwar's support for the campaign and denied they were working together.
Anwar indicated in the letter that his own "kind and generous disposition" towards Dr Mahathir was not reciprocated and instead Dr Mahathir repeated the "scurrilous attacks".
Some said that Anwar is also anxious about his continued relevancy, especially given that the very man responsible for his downfall is now playing a leading role in the Opposition coalition.
But his letter from prison has tugged at the heart-strings of the PKR crowd. He spoke of his loneliness and depression in prison and how he finds solace in poetry.
"The letter was quite emotional in parts, it touched me," said a young PKR leader from Selangor.
Some in PKR see the letter as timely advice, some view it as a warning while others think it is a gentle admonishment of certain PKR leaders.
Anwar fears being forgotten, he feels neglected, ignored and even betrayed by those around him. He complained about how an earlier letter he sent to the PKR political bureau had not been taken seriously.
Well, the latest letter has had a sensational effect and it will affect his party's role in what he sees as Dr Mahathir's campaign.
Read also: Najib: Dr M's behaviour is expected