NEW YORK, June 28 (Reuters) - London-based law firm Herbert Smith and Australia's Freehills announced Thursday that they are merging into a single firm that will have 2,800 lawyers in 20 offices worldwide, as well as anticipated offices in New York, Germany and South Korea.

The new firm, Herbert Smith Freehills, will launch on Oct. 1, according to a statement from the two firms. The merger is subject to regulatory approval.

When the merger is complete, the firm will be one of the largest firms in the fast-growing Asia-Pacific legal market, and the eighth-largest firm worldwide based on the number of total lawyers, the statement said.

The merger is the latest in a string of recent tie-ups involving Australian firms. In December, Chinese firm King & Wood confirmed plans to merge with Australia's Mallesons. In September, UK-based Ashurst announced that it would merge operations with Australian firm Blake Dawson under the Ashurst name.

David Willis, the managing partner of Herbert Smith, said the merger is intended to capitalize on what he called the shift of economic power from West to East as more global companies eye the opportunities and challenges of expanding in the Asia- Pacific market.

"So many of our clients ... operate in global markets, and they're increasingly looking for global capability across a single platform," Willis said in an interview. "We think we are creating the leading fully integrated platform in Asia. It's very exciting, in terms of what we can offer our clients."

Willis and Freehills managing partner Gavin Bell will serve as joint CEOs of the new firm, working alongside a global governing council comprised of partners from both firms. The firm will have offices in Australia, Asia, Europe, the Middle East and the UK.

Willis said the firm will not have a single international headquarters. Instead, it will be organized around global practices with focuses on energy and resources, mergers and acquisitions, private equity, capital markets, infrastructure, banking and finance.

Over the next several years, the firm hopes to launch offices in South Korea, Germany and New York. The New York office, the first foray into the U.S. for both Herbert Smith and Freehills, would provide "fairly focused" North American-based support to clients on issues like international arbitration, investigations and anti-corruption matters and other cross-border issues, Willis said.

(Reporting by Jessica Dye)

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