BUENOS AIRES, Feb 14 (Reuters) - Agricultural exporting

firms in Argentina, one of the world's largest food suppliers,

are urging the government to quickly re-do a tender process for

a contract to maintain a key river route used to transport crops

after the previous call fell apart this week.

Argentina exports 80% of its grains through the Parana River

waterway, a route currently dredged by Belgian firm Jan de Nul.

Agro-export companies have previously requested the river be

dredged even further to boost the flow of ships.

Jan de Nul did not participate in the most recent tender

process, which prosecutors described as riddled with

irregularities and causing officials to scrap the auction

altogether.

Presidential spokesman Manuel Adorni said the government had

asked the competition watchdog to investigate "possible pressure

from the sole bidder," Belgian dredger DEME Group.

"We cannot delay this issue any longer," said Gustavo

Idigoras, the head of Argentina's agricultural export chamber,

on Thursday evening.

"We want the government to reopen the process, refine the

tender, in three months issue a new call for bids so that three

months after that it hears offers," Idigoras told Reuters.

DEME said this week it did not know why others had not bid

in the process. Last month, DEME had complained that the terms

of the auction unfairly benefited competitor Jan de Nul.