New York-listed boxship owner Seaspan is stepping up diversification efforts through a new LNG cooperation deal with China's Cosco Shipping Energy Transportation (CSET).

It has signed a framework agreement for a strategic alliance with the state-owned company, which has the largest LNG carrier fleet in China.

Both parties are committed to strengthening their "exchange of and collaboration on opportunities relating to LNG investments, LNG projects, LNG transportation, ethane transportation, or other related and mutually beneficial projects," Seaspan said.