Hong Kong (CNN) -- Taiwan's de facto representative offices in Hong Kong and Macau -- China's two special administration regions (SAR) -- will come out of hiding this week after operating incognito for nearly 45 years, a move that experts say defines a thawing of historically frosty cross-strait relations. Functioning in Hong Kong under the moniker of the "Chung Hwa Travel Service" since the 1966 Chinese Cultural Revolution, the office has often been mistaken as a private travel company because of its title, said James Shi Chu, Taiwan's Director General of Hong Kong & Macau Affairs. The new office will be renamed and upgraded on July 15 to the Taipei Economic and Cultural Affairs office, a title indicative of its true functions, Chu said.
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The renaming of Taipei's hub in Hong Kong delineates a warming of relations with Beijing
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Taiwan is Hong Kong's fourth largest trading partner, with a value of more than US$35 billion
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Taiwan President Ma Ying-jeou has been largely friendly toward mainland China since his election
Contact between China and @placeholder -- a self-ruled island -- has historically been defined by instability and limited diplomatic communication, Cheng said.