ALGIERS The party at the heart of power since Algeria's independence from France is convulsed by an internal revolt that may be an early skirmish in the battle to succeed 75-year-old President Abdelaziz Bouteflika.
Less than a month before the National Liberation Front, known by its French initials FLN, competes in a parliamentary election, an influential faction within the party has tried to oust Secretary-General Abdelaziz Belkhadem.
Belkhadem is a close ally of Bouteflika and is viewed by many as a potential successor, despite opposition to this from other powerful forces within Algeria's ruling elite.
"I wonder if the crisis inside the FLN is not linked to the next presidential election, and that the target is Belkhadem as a potential candidate," political analyst and writer Abed Charef told Reuters.
The FLN was the movement which fought French colonial rule and, after independence in 1962, it ruled in a one-party system, coming to be known as "the state within the state".
With echoes of the Soviet Communist Party, the constitution for years contained an article requiring any senior official to be an FLN member.
Though the FLN lost some of its status 20 years ago when Algeria adopted a multi-party system, even now it is seen as the "party of power". Bouteflika is honorary chairman of the FLN and most government ministers are members.
But in the past few weeks, a fight for control that at times verged on farce has eclipsed the FLN's august traditions.
When the rebel faction tried to hold a session of the FLN's central committee to vote no confidence in Belkhadem, they found that Belkhadem's loyalists had locked the doors of the party's national headquarters, a Moorish villa in the capital, Algiers.
The party dissidents held a brief protest in the front garden of the building, shattering the calm of the street in the up-market Hydra district where the headquarters is located.
The mutiny is now on hold after Interior Minister Daho Ould Kablia intervened and said the issue would be reviewed after the May 10 parliamentary election. But that is likely to be only a temporary reprieve for Belkhadem.
Abdelhamid Si Afif, a member of the FLN's political bureau and chairman of the foreign affairs commission in parliament, says the party chief must go.
Belkhadem's opponents accuse him of being autocratic, too close to wealthy business interests and detrimental to the party's popular appeal.
"He handles the party as if it was something he owns. He excluded valuable activists from running (in the election). He should quit because if he stays the FLN will disappear," Si Afif told Reuters.
Belkhadem denies the allegations, dismissing the FLN rebels as a minority pursuing personal interests, not the party's.
The actions of Belkhadem's opponents will have "the impact of a damp squib", said Kassa Aissi, a member of the FLN's political bureau and an ally of the party leader.
Belkhadem "remains and will remain" head of the party, Aissi told local media.
Behind the scenes in the contest over Belkhadem's future lies a bigger consideration: who replaces Bouteflika.
Few Algerians expect him to seek a fourth term when his mandate runs out in 2014. He may even step down before then, some analysts say. He has a history of illness and has appeared frail in his tightly-controlled public appearances.
Belkhadem is a leading candidate. He is one of the few senior figures in the secular establishment who is liked by powerful Muslim clerics.
He also has the backing of the president, enjoys the title of Bouteflika's personal representative and often attends functions on the president's behalf.
Asked whether Belkhadem would run for the presidency if it fell vacant, FLN heavyweight Abderrahmane Belayat, told Reuters: "Perhaps, maybe."
"We must have our man in the next presidential election. What if our competitor Ahmed Ouyahia, who is currently prime minister and leader of the National Rally for Democracy, will run, should we stay away?"
However, a strong camp within the ruling elite, backed by the military, does not want Belkhadem to be president.
This faction believes he is too sympathetic to Islamists, a group it views with suspicion because Algeria is still emerging from a conflict between the security forces and hardline Islamists in which an estimated 200,000 people were killed.
And it wants a clean break with Bouteflika's rule when he steps down, not a continuation.
Whoever replaces Bouteflika must first win a presidential election. But gaining the endorsement of the institutions of the ruling elite gives a candidate a big advantage, which is why the stakes are high in the battle being fought out now.
Belayat, a former minister who is a member of the FLN's political bureau, says much will depend for Belkhadem on how the party performs in the May 10 parliamentary election.
The FLN is competing against an unprecedented number of parties after Bouteflika, under pressure following last year's popular Arab uprisings, opened up the political space.
"We will have more clarity after the elections. If Belkhadem conserves the majority (in parliament), he will become the big winner, and his troubles with influential members of the party will end. But if he loses the pole position, he will have to quit," Belayat told Reuters.
The vote could also be a decisive moment for the FLN itself. For all the party's historic role, some influential Algerians think a monolithic party of power is out of step with the country's ambitions to modernize and reform.
"If the FLN falls, the state will review its position towards it. The party will become a small party, and its members will quit, seeking positions in other parties," Belayat said.
(Editing by Christian Lowe and Alistair Lyon)