Analysts had predicted an attempted military coup after Mr Conte died
The head of Guinea's army has said that plotters trying to launch a coup after the death of President Lansana Conte do not represent most troops.
An army statement issued earlier said that government had been dissolved, hours after President Conte's death.
But Guinea Prime Minister Ahmed Tidiane Souare denied this and said the government "continues to function".
The African Union is to hold a crisis meeting on the coup attempt, which has been widely condemned.
Seeking to downplay the significance of the events, Guinea's armed forces chief, Gen Diarra Camara, told French TV station France 24 that the coup leaders did not have widespread support.
"I think they are in the minority. They are not the majority in the army," he said.
National Assembly Speaker Aboubacar Sompare, who - according to Guinea's constitution - should be in charge of the country until an election is held within 60 days, also said he did not think the entire military backed the putsch plot.
But a military source told the BBC's Alhassan Sillah that only a small minority of soldiers were opposing a military takeover.
Coup leaders were trying to win over these loyalists at a meeting at the Alpha Yaya Diallo military base in the capital, Conakry, the source said.
The BBC's West Africa correspondent Will Ross says a power struggle in the army could be extremely dangerous given the country's ethnic divisions.
Tanks have been seen throughout Tuesday on the streets of the Guinean capital, Conakry.
President Conte, who ruled the West African country with an iron fist for 24 years, died on Monday night after a "long illness", it was announced in the early hours of Tuesday.
The cause of his death is unknown, but Mr Conte, 74, was a chain-smoker and diabetic who is also believed to have suffered from leukaemia. Forty days of national mourning have been declared.
Guinea's neighbours - Liberia, Sierra Leone and Ivory Coast - are enjoying relative stability after years of conflict and there are fears any unrest there could spread and embroil the sub-region in fighting once more.
But just hours after the the president's death was announced, a junior officer went on state radio to say the army had taken over, and a body called the National Council for Democracy and Development (CNDD) had been set up.
"As of today, the constitution is suspended," said Capt Moussa Dadis Camara. "The government and the institutions of the republic have been dissolved."
Capt Camara, who is head of the army's fuel supplies unit, said an interim council would be set up to root out corruption and organise fair elections.
Ministers were later ordered to present themselves at the Alpha Yaya Diallo military base "to guarantee their security", while civilians were told to stay indoors and refrain from looting.
The African Union, European Union and United States led condemnation of the move.
"This seizure of power constitutes a flagrant violation of the Guinean constitution," African Union commission chief Jean Ping said in a statement.
Mr Ping called for an urgent meeting of the 53-member bloc in the Ethiopian capital Addis Ababa on Wednesday morning to discuss the situation in Guinea.
Relying on military
Former colonial power France - in its capacity as the current holder of the European Union's rotating six-month presidency - said it would oppose any attempted putsch in Guinea.
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Washington called for a "peaceful and democratic transition" in Guinea.
The BBC's Alhassan Sillah said soldiers have set up check-points along the main roads into the city centre, but so far there have been no reports of them being heavy-handed.
Vehicles are checked briefly and waved through, he says.
The BBC's Will Ross says many analysts had predicted the army would try to take over following Mr Conte's death because he had been increasingly relying on it to shore up his oppressive rule.
Despite Guinea's mineral wealth, it is one of West Africa's poorest nations
General Conte came to power in 1984 at the head of a military coup to fill the vacuum left by the sudden death of his predecessor, Sekou Toure, who had been president since independence from France in 1958.
He eventually oversaw a return to civilian rule and was elected three times, although critics said the votes were never free or fair.
As his health declined over the last five years, it was often unclear who was in charge and the government barely functioned, our correspondent says.
Although Guinea's mineral wealth makes it potentially one of Africa's richest countries, its population of about 10 million is among the poorest in the region.