UNITED NATIONS (AP) – The U.N. Security Council on Monday formally nominated South Korean Foreign Minister Ban Ki-moon to succeed Kofi Annan as United Nations secretary-general, all but assuring that the quiet diplomat will become the eighth chief in the world body’s 61-year history.

What would have been an event of major significance – Ban will become one of the world’s best-known and most influential diplomats over his five-year term – was overshadowed by North Korea’s claim that it had conducted a nuclear test.

“This should be a moment of joy. But instead, I stand here with a very heavy heart,” Ban said at a news conference in Seoul. “Despite the concerted warning from the international community, North Korea has gone ahead with a nuclear test.”

Ban, who participated in six-party talks with the North in 2005, vowed to help resolve the North Korean nuclear crisis after he becomes secretary-general. He must be approved by the 192-nation General Assembly, which has never rejected a Security Council nomination.

Japan’s U.N. Ambassador Kenzo Oshima asked the General Assembly to act promptly to give final approval to Ban so he can have a sufficient transition before taking over as U.N. chief on Jan. 1, after Annan’s second five-year term ends.

“I think the fact that the candidate is currently foreign minister of the Republic of Korea is an asset in dealing with the situation in the Korean peninsula that we are now facing,” he said.

Some diplomats speculated that North Korea may have conducted the test when it did partly to signal its disapproval for Ban. The North has not publicly commented on his bid but has accused him of blindly following the U.S. line by urging the North to resume negotiations and give up the atomic weapons program.

Normally the 15-member council would vote on a nomination, but Britain’s Ambassador Emyr Jones-Parry suggested in Monday’s meeting that Ban be approved by acclamation, done when there are no dissenting votes.

The idea was greeted with applause from the other ambassadors, diplomats who attended the meeting said.

Unlike in previous years, Ban’s selection was marked by an absence of rancor or political infighting.

He was the front-runner in all four informal polls the Security Council conducted, never getting fewer than 13 votes in favor of his candidacy.

The final straw poll last week revealed that he had the support of all five veto-wielding members of the council, and the remaining five candidates quickly left the race.