UPDATE 1-Senior U.S. State Dept official to visit Taiwan for weekend memorial service

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By David Brunnstrom

WASHINGTON, Sept 16 (Reuters) - U.S. Undersecretary for Economic Affairs Keith Krach will visit Taiwan for a memorial service for former Taiwanese President Lee Teng-hui on Saturday, the U.S. State Department said, a move likely to anger Beijing at a time when U.S.-China ties are at their lowest ebb in decades.

"The United States honors President Lee's legacy by continuing our strong bonds with Taiwan and its vibrant democracy through shared political and economic values," a State Department statement announcing Krach's trip said on Thursday.

The announcement had been widely expected after the senior U.S. diplomat for East Asia, David Stilwell, said last month that the United States would bolster ties with Taiwan by establishing a new economic dialogue with the island. He said subsequently that Krach would lead it.

The State Department statement made no mention of the dialogue.

On Monday, China's Foreign Ministry spokesman Wang Wenbin was asked about the possibility of a visit by Krach to Taipei and said China firmly opposed official exchanges between the United States and Taiwan, while warning of serious damage to China-U.S. relations.

U.S. Health Secretary Alex Azar visited Taiwan last month, the highest level U.S. official to travel to the island since Washington broke off diplomatic ties with Taipei in favor of Beijing in 1979.

Lee Teng-hui, who died on July aged 97, was dubbed "Mr. Democracy" for burying autocratic rule in Taiwan in favor of freewheeling pluralism. He thrived on defying China's drive to absorb an island it regards as a wayward province.

The United States, like most countries, has official relations with Beijing, not Taiwan, but Washington is bound by law to help Taiwan defend itself and is its main arms supplier.

Reuters reported earlier on Thursday that the United States plans to sell as many as seven major weapons systems, including mines, cruise missiles and drones to Taiwan, as President Donald Trump ramps up pressure on China ahead of his November re-election bid. (Reporting by David Brunnstrom and Tim Ahmann Editing by Chizu Nomiyama and Jonathan Oatis)