Updated

The consortium carrying out a historic expansion of the Panama Canal says it may have to suspend work due to financial problems caused by a $1.6 billion cost overrun.

The group issued a statement Wednesday giving the Panama Canal Authority 21 days to settle the dispute, but says it will continue working in the meantime.

Canal Administrator Jorge L. Quiuano responded with his own communique saying the Authority will continue to demand the companies "respect the contract that they themselves accept and signed."

The consortium is formed by Spain's Sacyr Vallehermoso, Impregilo of Italy, Jan De Nul of Belgium and Constructora Urbana SA of Panama. It won the construction contract with a $3.2 billion bid in 2009 — about $1 billion less than authorities had estimated the expansion would cost.