China said yesterday it would retain "absolute control" over seven sectors it considers critical to national security. Armaments, power generation and distribution, oil and petrochemicals, telecommunications, coal, aviation and shipping were listed by state media yesterday as "strategically important sectors". They have been vaguely defined since the 1990s. "State capital must play a leading role in these sectors, which are the vital arteries of the national economy and essential to national security," State Assets Supervision and Administration Commission (SASAC) Chairman Li Rongrong said Monday. "In these key sectors, state-owned assets should expand in volume and optimise in structure, and some key enterprises should grow into leading world businesses." SASAC anticipates that between 30 and 50 large business groups capable of competing globally could emerge in these areas.