Term limits were embraced across Africa as a check on presidents with dictatorial ambitions. Little wonder, then, that a proposal to change Nigeria's constitution to allow the president a third term has sparked raucous debate.

Amid dire warnings and apocalyptic headlines, the proposal has split President Olusegun Obasanjo's own party and set various tribes and religious groups against one another in a country already fraught with tensions that often explode into deadly violence.

Obasanjo has not said whether he wants to run again, but his allies are pushing for a third term. Vice President Abubakar Atiku, a former Obasanjo ally who wants to contest the 2007 election, has become a leading opponent of what some see as a plot to make Obasanjo president for life, derailing Nigeria's budding democracy. The West African nation of some 130 million people was ruled by military dictators for 29 of the 45 years after its independence from Britain.

The United States is strongly opposed to a third term, while Britain has indicated support for the idea. Both are close to Africa's most prolific oil producer, the world's eighth-largest producer of crude and fifth-largest supplier to the United States.

Diplomats say they are concerned about the message an Obasanjo victory would send to other African countries battling to break out of the cycle of lifetime presidencies. Nigerian newspapers have run editorials praising South African President Thabo Mbeki for promising to stand down when his second term expires, and urging Obasanjo not to follow the route of Uganda's President Yoweri Museveni, who changed the constitution and won a third term this year.

Last week, Obasanjo supporters presented a constitutional amendment bill to Parliament that includes the proposal to extend the two-term limit to three. Debate is set to begin next month.

If passed by two-thirds of both houses of Parliament and in the 36 state legislatures, the amendment would allow Obasanjo to contest elections and serve another four years. The next Nigerian leader could govern for 12 years.

Supporters point to Obasanjo's economic reforms and fight against corruption that transformed the country from a pariah on the world stage with negative growth to a favored son that within a week will be practically free of a $35 billion foreign debt under debt forgiveness and debt buyout schemes. Finance Ministry officials project economic growth of more than 8 percent.

While Obasanjo has not declared his candidacy, he told The Washington Post this month that "God is not a God of abandoned projects," apparently arguing he needs more time to complete his reforms.

Potential opponents are seen as lackluster, among them former military strongmen — like Obasanjo — or politicians who came to prominence under the years of military rule, like Atiku.

If Obasanjo runs again and wins after constitutional procedures have been followed, it would be no threat to Nigeria's democracy or its unity, said Chief Olabode George, deputy chairman of Obasanjo's party.

"For me, it is not a matter of life and death the way others are trying to rake it up," he said.

In an interview Wednesday in London, Information Minister Frank Nweke said members of the opposition and "disgruntled politicians" were driving the debate over term limits. Even if the amendment is adopted, he said, the final word on whether Obasanjo gets another term "will be the prerogative of the Nigerian people.

"It remains a democratic process," Nweke said.

Many Nigerians, though, feel similarly to students who protested in the northern city of Kano Tuesday, waving placards demanding "End Dictatorship Now!" and "Obasanjo Must Go!"

"Is Obasanjo saying he is the only one that can save Nigeria? Even Jesus Christ who came to save the world did what was required of him and left!" said Martins Eze, who was among the hundreds of protesters.

Nigeria has recently suffered fatal riots between Christians and Muslims and attacks on the oil industry by southern militants demanding a greater share of oil wealth. Militants among the Igbo tribe have also resurrected agitation for independence in the east, nearly 40 years after an Igbo attempt to secede was crushed in a civil war.

From independence in 1960 until 1999, Nigeria was ruled almost exclusively by Muslim soldiers from the arid north who plundered a treasury bloated by oil pumped from the largely Christian south. Obasanjo is a southern Christian.

Of Nigeria's foreign allies, the United States has been most strident in its opposition to a third term, despite good relations with Obasanjo. The State Department said this week that "executive term limits should be respected in the interests of institutionalizing democracy and opening political space ... (through) a regular turnover of power."

Introducing the debate in Britain's House of Lords on Tuesday, Lord Waverley argued against foreign pressure: "International pronouncements about constitutional change unleashing turmoil and conflict are somewhat premature."

What was important, he added, was "safeguarding a democratic outcome to the constitutional amendments, recognizing Nigeria has come of age and is now master of its own destiny."