UNITED NATIONS — The U.N. Security Council has signaled its intent to speed up the decision-making process by uniting behind a procedure that could, by today or Monday, name the South Korean foreign minister, Ban-ki Moon, as Secretary-General Annan’s successor at Turtle Bay.

A group of powerful council members, including the American ambassador to the United Nations, John Bolton, and the Chinese ambassador, Wang Guangya, had wanted to conduct a potentially decisive vote as early as today. But Britain, which is said to be lukewarm about Mr. Ban’s candidacy, argued yesterday that such a vote would be unfair to two candidates who joined the race just last week.

The 15 council members decided to conduct a fourth blind straw poll on the seven declared candidates today. On Monday, however, they will take another poll, using different rules, which could turn out to be the final crowning of the front-runner.

“We’ve reached that time in the decision-making process,” Mr. Bolton said. “We’ve said for some time that we would want to reach this decision by the end of September, early October.”

According to yesterday’s decision, Monday’s vote will be cast on color-coded cards that identify the voter either as one of the 10 elected members of the council or as one of its five permanent members. The five — America, China, Russia, Britain, and France — have a veto. A candidate that meets no opposition from them is assured the council’s support, which could well seal the selection process.

“The process that was decided is fine by us,” a British official who requested anonymity said yesterday. Britain only required that the two new candidates — a former Afghan finance minister, Ashraf Ghani, and President Vike-Freiberga of Latvia — be treated fairly, he added.

Both entered the race after the five other declared candidates had been tested by at least one blind straw poll. In the latest such poll, Mr. Ban emerged as the leading candidate, with only one council member voting to discourage his campaign.

Monday’s straw poll will not be necessary if that member changes its vote today and no other member turns against Mr. Ban. Otherwise, the rule change significantly raises the stakes for the council members, as well as for the candidates.

“Now if someone goes in, they will know that the next [poll] is” color-coded, the French ambassador to the United Nations, Jean-Marc de la Sabliere, told reporters yesterday.

Council members have not disclosed their voting patterns, though several diplomats and officials have said the Bush administration supports Mr. Ban’s candidacy, as does Beijing. While Britain is not believed to have cast an opposing vote, it is said to favor a Singaporean candidate that has yet to enter the race.

If Mr. Ban overcomes all the remaining opposition, he most likely will receive the council’s blessing as its rotating presidency is assumed by Japan, a historic nemesis of South Korea, sealing a symbolic unification of the world’s support.

The outgoing council president, the Greek ambassador to the United Nations, Adamantios Vassilakis, said yesterday that he has talked to his Japanese counterpart, Kenzo Oshima, about the possibility that a final decision will be taken in October. “I was not going to take anything from them,” Mr. Vassilakis said.