TAIPEI, Feb 8 - Taiwan believes its recent detente with China will not be derailed by a deal to buy U.S. weapons, despite Beijing's expressions of outrage towards Washington at the sale, a senior official said on Monday.

The island's top negotiator, P.K. Chiang, said he did not expect China to punish Taiwan over the proposed $6.4 billion arms package, including Patriot missiles and Black Hawk helicopters, allowing talks between the political rivals to remain on track.

''This is not a new topic, so I believe there won't be any impact on the present cross-Strait dialogue or on future development, and I've not received any news on this subject,''Chiang told a news conference.

China has claimed sovereignty over Taiwan since 1949, when Mao Zedong's forces won the Chinese civil war and Chiang Kai-shek's Nationalists fled to the island.

Beijing has threatened to attack democratic Taiwan if it tries to formalise its de facto independence.

But since China-friendly Taiwan President Ma Ying-jeou took office in 2008 the two sides have signed 12 trade and transit deals.

Negotiations on a free-trade style deal, the biggest item between the two sides this year, could produce an agreement in early 2010 as expected, Chiang said.

That deal, dubbed an economic cooperation framework agreement, would cut tariffs between economic powerhouse China and export-reliant Taiwan.

It could also open the often isolated island to trade pacts with other markets, especially in Asia.

China has blasted the United States over the planned arms package for Taiwan, saying it would place sanctions on U.S. firms that sell weapons to the island.

Taiwan seeks advanced foreign-made weapons to update its military, which has begun to lag China in the balance of power due to a massive increase in Chinese defence spending and investment in more high-tech fighters and warships.

Washington switched diplomatic recognition from Taipei to Beijing in 1979, but is obliged by the Taiwan Relations Act of the same year to sell Taiwan weapons it needs to defend itself.