Maj. Gen. Ibrahim Babangida, who has led this coup-plagued nation of 100 million people for only six weeks, said in an interview today that the Nigerian people will not give him much time before he must turn around the country's crumbling economy.

Accordingly, the 44-year-old former tank commander said, his government is scrambling, on its own, to reschedule unpaid debt that threatens to cut Africa's most populous country off from essential imports and to prepare for an expected precipitous drop in the price of Nigeria's key export, oil.

He said he expected a reduction soon in the price of Nigerian oil, upon which the country depends for about 96 percent of its foreign-exchange earnings. Nigerian crude now sells for about $28 a barrel, but some oil analysts predict that the Organization of Petroleum Exporting Countries' price war could lower prices considerably.

"Once such a thing happens, we must be prepared to accept it," Babangida said. "It is one of the reasons it is necessary to diversify the economy. So we shift the emphasis from oil to other commodities."

The International Monetary Fund is offering Nigeria a multibillion-dollar bailout, but weeks of national debate on whether to accept the loan have made it clear that the people of this West African country would rather go it alone. Acceptance of the loan and the stern conditions that come with it are seen here as an abrogation of Nigeria's sovereignty.

"If the country is determined to do without it, fine," the career military officer, who has taken the title of president, said in an interview with three American journalists.

Babangida's statement appeared to mark a retreat from his declaration shortly after taking power that he would break a two-year-old deadlock with the IMF on an agreement that would unlock about $5 billion in urgently needed loans.

In the course of a decade, with the explosion and then the fizzle of oil prices, Nigeria has gone from being black Africa's most conspicuous consumer to being its biggest, most unapologetic debtor.

In the interview, Babangida said his government has taken steps to improve relations with the United States.

"We did indicate officially that we did want to get closer," said Babangida, who noted that relations had deteriorated during the 20-month rule of his predecessor, Maj. Gen. Mohammed Buhari. Buhari is in detention in Lagos, and his conduct as head of state is under investigation by a panel appointed by Babangida.

Babangida said he hoped better Nigerian-U.S. relations would make it possible for the United States "to show some degree of understanding" for Nigeria's severe debt problem. The United States is Nigeria's third-largest trading partner, after Britain and France, and a major consumer of Nigerian oil.

Babangida said he had fond memories of his year of U.S. Army Armor School training at Fort Knox, Ky., in 1972. "I went to Fort Knox. I didn't get to get into the bullion reserves they have there," he said with a laugh, "but I enjoyed it. I'm an armored man."

Nigeria owes about $22.5 billion in foreign debt, but more than a third of that is in short-term loans that the government has been unable to pay on time. The central bank is more than three months behind in releasing hard currency to pay off business creditors, and most U.S. and European banks in recent weeks have been refusing to do business with Nigerian importers.

Babangida said his government is trying to persuade commercial banks to reschedule the short-term trade debt incurred in recent months. "I want to believe that we should be able to sort of agree with the need to do the rescheduling," he said.

Last year Nigeria made a similar rescheduling agreement with commercial banks on about $8 billion worth of overdue loans. Only about $800 million of that debt has been paid off so far.

Babangida acknowledged the seriousness of Nigeria's debt problems, as compounded by declining oil revenues, but he maintained that Nigeria "shouldn't be in a hurry" to make a decision on matters such as the IMF loan.

One of the conditions of the IMF loan that Nigerians find most objectionable would be a sharp devaluation of the currency, the naira, which trades on the black market at about one-fourth its official value.

International lending agencies, western bankers and Babangida's finance minister insist that devaluation must occur for Nigeria to rebuild its moribund farm and industry sectors.

Last week, Babangida declared a 15-month "economic emergency" during which Nigeria is to try to increase food production and manufacturing. Today, the president of this West African country, which has had six military coups and three leaders assassinated since 1960, said his government must show "positive results" within that period or risk losing public support.

He said Nigeria, which 20 years ago was a major food exporter but is now a food importer, "should be very, very self-sufficient in food" by this time next year.

Last week Babangida promised that he would introduce a plan in 1986 for a return to civilian government, but he said today that he had given no thought to the possibility of running for office himself.