Citic Telecom International Holdings Ltd, part of the Chinese state-owned Citic Group ventured into Macau to buy the British Cable & Wireless Communications (CWC) and Portugal Telecom (PTC) for $1.2 billion.

The deal will help the company gain access to Macau's growing telecom consumers. Citic Telecom said Monday that it would raise its stake from 20 to 99 percent in Telecommunicacoes de Macau and the remaining 1 percent will be held by Macau post office, according to the Associated Press.

Citic Telecom has been diversifying its customer and services profile from wholesale to a more consumer-focused services provider, reported Reuters.

Soon after the deal, shares in Citic Telecom surged to a two-year high in Hong Kong trading. Macau's revenue from casinos is five times more than that of the Las Vegas Strip, and it has 1.5 million mobile-phone users, about triple the size of its population, according to government data, reported Bloomberg.

Citic Telecom plans to fund the acquisition with internal resources. It has also secured some funding commitments from a group of banks and other financial institutions, according to the press release.

The company will benefit from the rising number of Chinese visitors using roaming services to call home while in Macau, chief financial officer David Chan said to Bloomberg. The city has a separate phone regime to the mainland.

"Macau has kept very good growth, mainly benefiting from inbound roamers," he said. "We will have good, enjoyable growth." Bloomberg further reported that the telecom company was the biggest gainer among the 355 stocks tracked by the Hang Seng Composite Index. It rose to 22 percent earlier in the day.

The telecom company also has its operations in the U.S., Brazil, Japan, Taiwan and other Asian markets.