MONTREAL - The Opposition NDP wants the Conservative government to end its silence over the future of Canada's busiest bridge.

The NDP's deputy critic for transport, Jamie Nicholls, says it has become essential for Ottawa to replace the Champlain Bridge, which connects Montreal with southern Quebec.

He told a news conference in Montreal on Monday that commuters and businesses can no longer afford the uncertainty surrounding the bridge's future.

Nicholls was joined by fellow NDP MP Hoang Mai, who says he has received hundreds of letter from residents in his south-shore riding demanding a new bridge.

To date, federal Transport Minister Denis Lebel has only said the government is studying all options.

It is estimated that roughly $20 billion in international trade crosses the Champlain Bridge each year. But recent engineering reports say the 49-year-old bridge is at risk of collapse and must be replaced soon.