Chinese government and other East Asian investment in UK waters should be welcomed for "breathing new life into the North Sea", an expert in the oil and gas sector has said ahead of a global conference in Aberdeen on the impact of giant national firms on the Scottish sector.

Next month's Offshore Europe conference will look at the role of the national oil companies in the next 40 years of North Sea production.

Ian Williams, head of accountant Campbell Dallas, said investment by the state-backed behemoths was a "vote of confidence" that Scots should embrace, not least because it helps the Scottish sector to disseminate skills to rising oil and gas areas such as Australia.

Williams, who also chairs the global energy group of the independent accountants' network UHY, said that the deep pockets of national oil companies such as China's CNOOC, Sinopec and the Korean National Oil Corporation, which have taken major stakes in North Sea companies recently, had already benefited the Scottish skills base.

"The shift away from the oil majors to the national oil ­companies of China, India, Malaysia and others seeking to secure their long-term future of supply has bridged an investment gap.

"These companies have brought with them a different culture, and the fact that they have done their diligence and want to invest here has been a huge vote of confidence in the future of the Scottish industry.

"It has breathed new life into the North Sea and in terms of cash for training and filling the skills gap, it has been enormously significant.

"The NOCs have not just secured an interest but they have gained global expertise that has impacted Scots mobility of labour, because where they have been able to buy into Scottish expertise, they have been able to gain easier access to the intellectual property as a consequence of their ownership."

Some industry commentators express alarm at the rise of Chinese activity in the North Sea.

But Williams said the fact that Chinese companies now own 8% of the North Sea production is good news, and a vote of confidence: "It's not a sign that we are being exploited like a third-world country. We have got to remain open and welcoming. [Foreign investors] are bringing new ideas and lots of cash that is otherwise not available to us."

According to analyst PLS, NOC acquisitions reached an all-time high in 2012 of $112.6 billion, amounting to 45% of global exploration and production and mergers and acquisition.

CNOOC recently announced a £9.7bn deal to take over Canadian rival, Nexen. Simultaneously, Sinopec announced it had a £970 million, 49% stake in Canadian oil firm Talisman's UK North Sea business.

Talisman has around 2500 staff and contractors in 11 North Sea installations.

In 2010, Dana Petroleum was taken over by the Korean National Oil Corporation, boosting production by 50% to 62,000 barrels a day and increasing revenues by 80% to £1.1 bn.

Held at the Aberdeen Exhibition & Conference Centre on September 3-6, Offshore Europe 2013 features exhibitors from 30 countries. More than 48,000 visitors are expected.