The latest ratcheting-up of tensions has seen senior members of the ruling UMNO party taking the - until recently, unthinkable - step of asking Mahathir to leave the party he headed for more than two decades.
While many UMNO members still express support for the man widely known as Dr M, the majority of the party apparatus in Mahathir's home state of Kedah have now publicly thrown their weight behind his successor.
In comments reported in Malaysian media over the weekend, Mahdzir Khalid, the state's chief minister, said he had lost confidence in Mahathir and called on him to give up his various advisory positions with government and state-owned agencies.
"If Tun [Dr Mahathir] wants to bash the government, it would only be proper for him to relinquish all these posts and be an independent individual who has nothing to do with the government," he said.
Kedah was Mahathir's power base when he was in charge of the country for over 22 years.
The chief minister's comments followed an open letter from Mahathir, posted on the internet on Saturday, continuing his criticism of Abdullah and the current government.
The row first erupted in April when Badawi cancelled plans to build what was to have been the Malaysian half of a new bridge to Singapore.
The new link was one of several so-called mega-projects approved when Mahathir was in office but cancelled by his successor.
Abdullah Ahmad Badawi
- Prime minister since 2003.
- Touts 'Mr Clean' image, but critics say has failed to tackle corruption.
- Father was founding member of UMNO.
- Was made deputy PM after Mahathir sacked predecessor, Anwar Ibrahim.
- Prime minister 1981-2003.
- Regarded as key force behind transformation of Malaysia into Tiger economy.
- Often criticised for ruthless silencing of opponents.
- Critical of Malays he said were complacent and failed to work hard.
That opened the way for Mahathir to launch a stream of allegations against the prime minister, including mismanagement of Proton, the national carmaker, and the alleged growing influence of Badawi's relations in obtaining government contracts and deals.
Analysts say Badawi himself has yet to provide satisfactory answers to many of these questions.
In his internet letter, Mahathir said he was attacking Badawi because "no one else is able to criticise the prime minister".
"The mainstream media, including radio and television, are not allowed to admonish the prime minister. Pre-paid telephones are now required to be registered so that anyone who transmits SMS will be known by the government and action can be taken."
The former premier said that unofficial restrictions on his speaking were so tight that he could not be invited to officiate at functions organised by UMNO, governmental and non-governmental organisations, and even universities.
Mahathir also said that party members and the public were advised against attending any function where he was speaking, adding that police and political leaders had made a variety of threats to scare off anyone who refused to comply.
Badawi has denied Mahathir's allegations.
There had been hopes that a much touted face-to-face meeting between four days before the Muslim Eid Al Fitr festivities would help to resolve the row.
Eid is traditionally seen as a time for forgiveness and harmony. In any case, open disputes are not a standard feature of the Malaysian political scene.
But the meeting on October 22 at Badawi's residence only served to reinvigorate Mahathir's campaign against the man he handpicked as his successor.
Commenting on the two-hour meeting, Mahathir said the prime minister had turned Malaysia into "a police state".
'Doses of venom'
Uncharacteristically, Badawi, who had until then largely taken Mahathir's attacks on the chin, hit back.
He described his predecessor's criticism as "stronger doses of venom", apparently upset that Mahathir had chosen to go public without waiting for his response.
"He has met me and said everything that he wanted to tell me. I have to take time to respond," Badawi said.
"However, he has repeated [the attacks] again ... this time with stronger doses of venom ... what to do? God only knows. It looks like he is intent on continuing what he has been doing all this while."
He then went on to list an almost point-by point rebuttal of Mahathir's accusations - a sign that the man, who for the past four months has held on to his "elegant silence", has had enough.
Shamsul Amri Baharuddin, a veteran political commentator and professor of anthropology at the National University of Malaya, said there was a feeling that Mahathir's attacks - particularly in the run-up to Eid - had won him few friends.
"The premeditatedness of Mahathir is actually making people very unhappy," he said. "He is all out to do some damage, he is not constructive at all and is informed by personal interests, not national interests."
"It doesn't seem like Abdullah is winning the battle of minds at the moment"
Fazil Mohamad Som,
World Islamic Economic Forum
Badawi himself has said the feud can only help the opposition, which was heavily defeated at the last elections.
Few analysts expect the row to produce any serious political instability, although some acknowledge that the face-to-face meeting was a mistake on Badawi's part.
"It doesn't seem like Abdullah is winning the battle of minds at the moment," said Fazil Mohamad Som, a political analyst at the Kuala Lumpur-based World Islamic Economic Forum.
"He made a blunder as prime minister by even meeting Mahathir. Mahathir is no longer a figure in power. So by holding talks with Mahathir, Badawi actually gave him much more credibility."
There is also a feeling that the row has begun to damage the country's image, adding to growing uncertainty about Badawi's leadership amid fears of an economic slowdown.
As Badawi begins his fourth year in office this week, many say that the present spat should not weaken the prime minister's position.
"It can weaken the party but it won't shake [Badawi's] position as UMNO leader and prime minister," said Mohamad Agos Yusoff, associate professor of political science at Malaysia's national university.
"All the cabinet ministers are with him and he has the support of state rulers."
"He is all out to do some damage, he is not constructive at all and is informed by personal interests, not national interests"
Shamsul Amri Baharuddin,
Now with senior UMNO officials calling for Mahathir to leave the party, all eyes are on the former leader to see how he responds.
"It's better he leaves UMNO," said Datuk Musa Sheikh Fadzir, UMNO division chief for the northern state of Penang. "It's alright for him to criticise the party when he is no longer a part of it."
But Fazil concedes it seems unlikely that Mahathir will give up the fight so easily.
"His end game is to basically get the projects that he worked on reinstated. He will go all the way to do this.
"Just like [Singapore's Minister Mentor] Lee Kuan Yew, Mahathir still wants a say on Malaysia. He still wants to play the game."