The government in Niger says demonstrations that blocked several polling stations Tuesday will have no impact on the eventual outcome of a referendum on ending presidential term limits.

Opponents of the referendum to allow President Mamadou Tandja to run for a third term successfully prevented several polling stations from opening in the western Tahoua region.

That is an area of strong support for opposition leader Mohamadou Issoufou, who condemned the referendum as a coup d'etat and called on all "sincere democrats and patriots" in Niger to mobilize against the vote.

Electoral Commission chief Moumouni Hamidou says none of those disruptions will affect the overall outcome.

Hamidou confirms that 30 polling stations in the western region were unable to open because of opposition demonstrations. But more than 1900 polling stations across Niger were open to voters, and he says that guarantees that referendum results will represent popular will.

Opposition leader Issoufou says the Tandja government did permit some anti-referendum rallies in the capital but restricted that campaign in rural areas where he says several activists were detained.

Six million of the country's 15 million people were registered to vote. Turn-out in the capital was light. But Communication Minister Mohamed Ben Omar says rural participation approached 75 percent, just as he says President Tandja expected.

With the electoral commission beginning to announce preliminary results on state radio, Omar says the final tally will not be known for three to five days given the problems of transport in such a large country.

President Tandja's term expires in December, and the constitution says he may not run again. This referendum is meant to remove that restriction and allow the 71-year-old leader to have another three years in office and run again after that if he wants.

The Economic Community of West African States is threatening to sanction President Tandja if he changes the constitution. The French Foreign Ministry says the referendum is outside Niger's constitutional framework. The European Union has suspended aid because it says the government is committing "grave violations" of the rule of law and democratic values.

Niger's parliament and its constitutional court both told the president that removing term limits would be illegal. President Tandja dissolved both bodies and now rules by decree.

Mr. Tandja says the referendum is a matter between himself and the people of Niger -- a direct dialogue that does not include his political opponents or the international community.