Since the time of its formation in April 2008, the Pakatan Rakyat has been criticised as amounting to little more than a marriage of convenience.
Indeed, apart from their common distaste for the current government and professed determination to rid the country of corruption and nepotism, it is hard to see exactly what the component parties in the opposition alliance have in common.
As the nation's two rival political groupings - the Pakatan Rakyat and the ruling National Front - prepare for possible snap polls later this year, opposition unity is likely to be tested still further.
The Pakatan Rakyat consists of three parties - the Islamist PAS, the secular Chinese-based Democratic Action party (DAP) and opposition leader Anwar Ibrahim's multiracial Parti Keadilan Rakyat (PKR).
Earlier this month, basic policy divisions were on display once again when Harun Taib, head of the Ulama Council of PAS, declared that one of the first priorities of the party if it won power in upcoming elections would be to implement hudud law.
Hudud refers to Islamic punishments such as stoning for adultery and flogging for drinking alcohol. PAS insistence on promoting hudud law has threatened the unity of the coalition since it was first established. The DAP is strongly opposed to hudud law, while the predominantly Malay PKR is caught in the middle.
Harun's statement triggered a flurry of denunciations from the DAP, particularly since the issue had apparently been settled some months before. Pakatan leaders held a three-hour meeting in September last year to thrash out the hudud issue. Party leaders subsequently announced that it was not part of the bloc’s policy to introduce hudud laws, and that any future move to do so would require the consensus of all three parties.
Responding to Hadi's more recent statement, DAP secretary-general Lim Guan Eng said any attempt to work outside the Pakatan framewok was tantamount to a “stab in the back”. “We respect PAS’ views on hudud, but our position is also very clear as we feel it is not in accordance with the Federal Constitution," he told the media.
Anwar Ibrahim later attempted to paper over the issue. All three parties, he declared, were committed to remaining united in heading towards the next general election. They would also maintain that unity if Pakatan were to form the next government.
In this, he appeared to have the support of PAS president Abdul Hadi Awang, who told the media after a meeting of the senior leadership at the PKR headquarters that Pakatan would adhere to the position announced in September 2011.
Not all PAS members are likely to be happy with the decision, however. Many may well be thinking along the lines of Harun, who suggested that PAS should consider changing its political allies if this would make it easier for the party to achieve its objectives.
General elections are not due in Malaysia until April next year, but there have been strong indications that it will be held in the second half of this year. The government has recently announced cash handouts for the poor, and amended several laws in an attempt to address opposition demands for greater civil liberty.
But while the timing of this latest rift in the Pakatan could weaken the coalition as it prepares for upcoming elections, the ruling National Front government will need to be careful about the way it attempts to take advantage of the issue.
UMNO, the dominant Malay-based party in the government coalition, is also trying to woo the Muslim vote. Thus, while pointing out opposition disunity, it cannot afford to come across as soft on Muslim issues.