MTR (HKG:0066) priced its HK$18.8 billion public bond offering, according to a statement Wednesday.

The corporate green bond issuance was structured as a triple-tranche offering consisting of HK$8.3 billion in five year 2.88% notes; HK$7.5 billion in 10 year 3.30% notes; and HK$3 billion in 30 year 4% notes.

Proceeds from the sale will be used to support "eligible green investments," the firm said.

The firm's inaugural Hong Kong dollar public bond issuance marks the largest bond transaction in the Hong Kong market, MTR added.

The public transport operator was previously reported to be seeking to raise HK$15 billion via the offering.