Germany's KfW IPEX-Bank is structuring the financing for a new AIDA Cruises vessel powered by LNG.
The 183,900-gt cruiseship is the third being built for the Carnival company at Meyer Werft in Germany.
The first entered service at the end of 2018.
"The green cruising concept means AIDA is the world's first cruise operator to run its new generation of ships on LNG, thus reducing the emission of CO2 and nitrogen oxides and completely avoiding the emission of soot particles and sulphur oxides," the lender said, without specifying the amount involved.
Carnival is the borrower, with financing backed by export credit insurance issued by the German state.
KfW will syndicate a "significant share" of the loan amount to an international banking consortium after signing of the agreement, it said.
