France says it does not support US plans for international sanctions on Sudan if violence continues in Darfur.
The humanitarian situation is worsening
The UN Security Council is debating a US draft resolution imposing sanctions on militias accused of "ethnic cleansing" against non-Arabs.
The US also hinted that the sanctions could be extended to the government.
Meanwhile, African leaders have urged Khartoum to stop bombing Darfur and say their proposed 300-strong force will have a mandate to protect civilians.
US Secretary of State Colin Powell says promises to reign in the pro-government militia, known as the Janjaweed, have not been kept by Khartoum so far.
"Only action not words can win the race against death in Darfur," he said.
Some one million people have fled their homes and at least 10,000 have been killed in what the UN calls "the world's worst humanitarian crisis."
A rebellion broke out in Darfur early last year, when two groups took up arms, accusing the government of ignoring the region.
"In Darfur, it would be better to help the Sudanese get over the crisis so their country is pacified rather than sanctions which would push them back to their misdeeds of old," junior Foreign Minister Renaud Muselier told French radio.
France led opposition to US moves at the UN over Iraq. As was the case in Iraq, France also has significant oil interests in Sudan.
Mr Muselier also dismissed claims of "ethnic cleansing" or genocide in Darfur.
"I firmly believe it is a civil war and as they are little villages of 30, 40, 50, there is nothing easier than for a few armed horsemen to burn things down, to kill the men and drive out the women," he said.
Human rights activists say the Janjaweed are conducting a genocide against Darfur's black African population.
Those who have fled their homes say the Janjaweed ride on horses and camels into villages which have just been bombed by government aircraft, killing the men and raping the women.
Sudan denies backing the militia and, under strong international pressure, has promised to disarm them.
Chairman of the African Union Commission Alpha Oumar Konare said that the 300 troops would arrive in Sudan by the end of July.
He said they would intervene if they saw civilians being killed.
"We have called for a halt to the bombings... We received promises today from Khartoum," he said.
Analysts say that at least 15,000 troops would be needed to bring peace to the vast area of Darfur.
The BBC's Barnaby Phillips says the African Union is determined to be taken seriously as a body devoted to solving the continent's problems, but is severely hampered by a lack of resources.
African leaders say they hope richer countries will also do their bit to help.
A draft UN resolution proposed by the US envisages travel and arms sanctions on Janjaweed.
A previous Security Council statement on Darfur failed to criticise Khartoum directly, after resistance from Pakistan and China, instead urging cooperation and the disarming of the Janjaweed.
Question of time
The Security Council met in closed session for several hours on Wednesday and the draft resolution is being discussed again on Thursday.
Council members disagree over how long the Sudanese government should be given to resolve the situation itself, says the BBC's Stephen Gibbs in New York.
Some countries, including Pakistan, say that Sudan should be allowed sufficient time to demonstrate that it means what it says.
The 'Janjaweed' militia are accused of ethnic cleansing
But the US remains sceptical over Sudan's commitment to act.
The US draft resolution threatens to escalate the sanctions within 30 days if results are not evident.
But diplomats hope that tough talking will force Sudan to act, our correspondent says.
They admit that imposing such a resolution on the largest country in Africa is fraught with difficulty, he says.