PetroChina, the country's largest oil and gas producer by output, said on Tuesday that new technological innovation has supported its development in the past five years, generating a profit of more than 100 billion yuan ($15.34 billion).

Qu Guangxue, the spokesman for PetroChina, said that China is not rich in oil and gas resources, so technological breakthrough plays an important role in driving the production growth in the past few years.

"We will continue to invest in research and technological expertise, because the country's complicated geology has made extraction difficult," he told reporters during a forum on the PetroChina's technological achievements from 2010 to 2015.

The company said that it has kept an annual oil production of more than 100 million tons for the past 21 years while gas production rose five fold from 18.3 billion cubic meters in 2000 to 95.5 billion in 2015.

At the same time, technological breakthrough is also a driving force for the Chinese oil major's overseas business.

The oil and gas production in overseas business reached 100 million tons per year. The crude oil transportation capability stands at 78 million tons while the company is able to transport a total natural gas of 60.4 billion cubic meters annually.

Qu said that the group has already invested more than $ 60 billion to the countries along the Belt and Road Initiative, accounting for 81 percent of the total overseas investment.

The Belt and Road Initiative refers to the proposal to build a Silk Road Economic Belt and a 21st Century Maritime Silk Road by Chinese President Xi Jinping.

"The initiative has provided a huge business opportunity for us, since we have cooperation with 19 countries along the Belt and Road initiative covering 49 oil and gas projects," he said.