By Joe Wallace

LONDON -- Ivan Glasenberg, the longtime chief executive of Glencore PLC, is handing over the reins of the global mining and trading giant he built, saying Friday he would retire in the first half of next year.

The Switzerland-based, London-listed company said it had tapped Gary Nagle, a senior deputy who currently runs the company's coal industrial assets, as his successor.

Mr. Glasenberg, a 63-year-old South African, joined Glencore in 1984 and has been CEO since 2002. He orchestrated the company's stock-market flotation in 2011 and shortly after merged it with miner Xstrata, transforming it from a privately held commodities trading business into a publicly listed mining and trading giant.

Two years ago, he started to lay out a timeline for when he might stand down, and more recently said it was getting close to time for him and his senior leadership team to step aside for the next generation of managers.

Mr. Nagle, currently based in Australia, plans to move to Switzerland in the new year to work on the transition to new leadership, Glencore said. He was widely seen as one of the front-runners to succeed Mr. Glasenberg.

"The old guys will be leaving," Mr. Glasenberg said on a conference call last December. "I don't want to be an old guy running this company -- and soon as those guys are ready to take over, I will move aside."

Mr. Nagle joined Glencore in 2000 and, like Mr. Glasenberg, worked his way through the company's coal business. From 2008 to 2013, he was chief executive of Prodeco, Glencore's coal operation in Colombia, before moving to South Africa to head the company's alloys assets until 2018.

"It's time to hand over to the new generation and a younger leader," Mr. Glasenberg told investors Friday, adding that he would retain his major shareholding in Glencore. "Gary can take this company forward in the future," he said of 45-year-old Mr. Nagle. "I'm happy to have him being the custodian of my shareholding in the company."

Founded as Marc Rich & Co. in 1974 by Marc Rich, the one-time fugitive trader, Glencore initially traded metals, minerals and crude oil. The U.S. attorney's office in Manhattan would eventually indict Mr. Rich, partner Pincus Green and the company on 65 counts, including buying oil from Iran during the 1979 hostage crisis. Mr. Rich and Mr. Green were later pardoned by President Bill Clinton.

The company became known as Glencore after Mr. Rich sold his stake in the early 1990s.

A former coal trader, Mr. Glasenberg took control of the firm's world-wide coal business in 1990 and spearheaded its dominant position in coal mining, snapping up operations in Colombia, South Africa and Australia.

After being named CEO in 2002, he quickly gained a reputation for being one of the mining industry's most astute deal makers. When he took Glencore public, he became a billionaire on paper. Mr. Glasenberg still owns a 9.1% stake in Glencore worth about $3.8 billion, according to data provider FactSet.

In 2013, he merged the then trading-focused Glencore with mining giant Xstrata in a $29.5 billion deal that created one of the world's largest coal, copper and zinc producers.

During his tenure, Mr. Glasenberg -- a champion racewalker -- also became known for his bluntness, aversion to personal publicity and hands-on management style. Once asked in an interview with The Wall Street Journal if the company had a work-life balance, Mr. Glasenberg said: "No. We work. You don't come here to take life easy. And we all got rich from it, so, you know, there's a benefit from it."

In recent years, Glencore has come under heavy scrutiny from U.S. authorities. It said in July 2018 that it had received a subpoena from the U.S. Justice Department, demanding records related to its compliance with American antibribery and money-laundering laws in Congo, Nigeria and Venezuela.

Glencore has also said it is the subject of an investigation by the U.S. Commodity Futures Trading Commission. It has said it is cooperating with both probes.

Glencore said in August that it spent $56 million in the first half of 2020 defending itself from various government investigations, including those undertaken by the Justice Department, CFTC, the U.K.'s Serious Fraud Office and Brazilian authorities.

Shares in Glencore rose more than 3% Friday. The announcement of Mr. Glasenberg's retirement came on a day when the company also said it planned to reduce its emissions to net zero by 2050.

Write to Joe Wallace at Joe.Wallace@wsj.com

(END) Dow Jones Newswires

12-04-20 1119ET