Chang did not reveal the capex for the 4G project but said outlays in the second half will be larger than in the first half.
Unicom had earlier earmarked about 80 billion yuan in total capex this year. It spent only 21.6 billion yuan in the first half, compared with 38.9 billion yuan in the same period a year earlier.
"In the second half we will invest in the trial 4G networks of FDD-LTE and TD-LTE, but the total investment will be capped under budget," Chang said.
The company posted a 55% rise year-on-year for its net profit for the first half, thanks to strong growth in 3G subscribers and increase in mobile data usage.
Net profit increased to 5.32 billion yuan ($868.7 million) for the six months ended June 30, from 3.43 billion yuan a year earlier. The latest results exceeded the average forecast of 4.89 billion yuan by four analysts polled by Thomson Reuters.
Revenue jumped 18.6% to 144.3 billion yuan. The company's 3G customer base grew 73.9% to over 100 million, while ARPU stabilized to 77.6 yuan. Mobile data usage meanwhile increased by 131.3%.
3G service revenue was up 52.1% to 40.91 billion yuan, representing a majority 56.2% of mobile service revenue.
The operator spent 4.22 billion yuan, or about 10% of its service revenue, on subsidies for 3G terminals. The proportion was down from 13% a year ago.
Trading in China Unicom's shares on the Hong Kong Stock Exchange were suspended on Thursday afternoon, because its first half results were unexpectedly posted on the State-owned Assets Supervision and Administration Commission (SASAC) before the Hong Kong market close. Unicom shares were up 2.67% to HK$11.54 prior to the suspension.
Chang apologized to investors yesterday in the press briefing and said such a mistake would not happen again.