The Panama Canal is taking reservations for ships to transit its new locks starting June 27, the day after the inauguration of a $5.25 billion project to double the waterway’s capacity, authorities said Monday.

The Panama Canal Authority said it processed 25 slots in the first hours since reservations opened. Four per day are reserved for super-large “New Panamax” vessels, as are the usual 25 a day for “Panamax” ships that pass through the old locks.

The first commercial slot went to a Japanese vessel carrying liquefied natural gas. Gas shipping between Asia and the United States is one of the new businesses that canal authorities are targeting with the expansion.

Canal administrator Jorge Luis Quijano said officials were pleased with the initial response and hope more and more ships will pass through the canal.

The inaugural passage through the expanded canal during opening ceremonies June 26 will be by a vessel chosen by lottery April 29.