PANAMA CITY - A $5.25-billion project to expand the Panama Canal had been completed by 46.5 percent, the authorities said Wednesday.

By the end of the third quarter of this year, some $4.28 billion had been invested in related contracts, the Panama Canal Authority (PCA) said in a report, submitted to the county's fiscal authorities as stipulated by a 2006 law.

The PCA, which took over the canal from the United States in 1999 under a treaty signed between the two countries, added that it had published 24 quarterly reports on the expansion project so far.

Last month, outgoing Panama Canal administrator Alberto Aleman Zubieta said the canal's expansion, designed to accommodate larger vessels sailing between the Atlantic and Pacific, would have an effect on current trade patterns.

Currently, nearly 5 percent of the world's shipping trade goes through the canal. The expansion project is expected to be completed by the end of 2014.