S&P Global Ratings has maintained The Hong Kong and China Gas' (HKG:0003) A- long-term issuer credit rating and subsidiary Towngas Smart Energy's (HKG:1083) BBB+ rating, according to a Thursday release.

The rating agency sees the subsidiary's strategic role for its parent as growing, with an expanding gas distribution and distributed solar segments in mainland China.

The subsidiary comprised 27% of the group's consolidated EBITDA last year, while the parent's stake in the subsidiary had risen to 68.38%.

The group sees stronger operating cash flow due to contributions from Towngas Smart Energy's renewable division, which partly offsets bottlenecks in gas distribution and fresh connection fees, S&P said.

The stable outlook reflects the rating agency's view that the companies will consider business growth hand in hand with financial soundness.

Significant changes in the companies' leverage, business mix, or strategic importance could trigger future rating actions.