China's Anbang Insurance Group has agreed to acquire Strategic Hotels & Resorts Inc for around $6.5 billion, as the owner of New York's iconic Waldorf Astoria expands its U.S. hotel portfolio, a person briefed on the matter said Saturday.

The deal, which illustrates corporate China's unquenched thirst for U.S. real estate, comes just three months after Strategic Hotels' current owner, private equity firm Blackstone Group LP, took the company private for around $6 billion.

The source asked not to be identified because the deal was not yet public. Anbang and Strategic Hotels did not respond to requests for comment, while Blackstone declined to comment. Bloomberg first reported on the transaction earlier Saturday.

Strategic Hotels' properties include the Four Seasons Washington, DC, on Pennsylvania Avenue, the Westin St Francis on Union Square in San Francisco and the beach-front Ritz-Carlton Laguna Niguel in Orange County, California.

Anbang purchased New York's Waldorf Astoria from Hilton Worldwide Holdings Inc in 2014 for $1.95 billion, one of the highest prices per room ever paid for a U.S. hotel. The deal closed in February 2015 following a review of by U.S. national security watchdog Committee on Foreign Investment in the United States (CFIUS).

At the time Blackstone took it private, Strategic Hotels owned 17 hotels operated by top hospitality chains including Hyatt Hotels Corp, InterContinental Hotels Group Plc and Marriott International Inc.

Chinese investment into hotels has been growing since 2011 and 2012, when just $160 million and $130 million were invested, according to data from JLL, a global real estate broker and advisory services company based in Chicago.

In November, Anbang agreed to buy U.S. annuities and life insurer Fidelity & Guaranty Life for about $1.57 billion.