As ships queue for days to transit the Panama Canal, the government in Central American country has announced it plans to double the capacity of the 92-year-old waterway that cost more than 20,000 lives to build.

The country plans to invest $5.25bn to allow ships more than twice the size of the current maximum to use the canal.

Final agreement is still some way off, but plans drawn up by the Panama Canal Authority before being passed to president Martín Torrijos to be voted on by the Panamanian legislature and ultimately going to public referendum for approval.

According to PCA chairman Alberto Alemán Zubieta, it is hoped work will begin next year with completion targeted for 2014. Expansion will be paid for through canal tolls, he said, although a bridging loan will also be required.

Meanwhile, queues at either end of the canal in recent weeks are reducing, according to the authority. Earlier this week, there were up to 40 ships waiting at either end of the canal, down from 111 ships in total on one day last week.

Waiting times have reached record-breaking levels - up to nine days - for some ships.

Some 40 ships transit the canal daily of which 25 have reservations and the remaining 15 pass strictly in order of arrival.

Maritime trade analysts suggest that problems of land cargo transport since Hurricane Katrina last year are causing the delays and many operators are seeking alternative routes.