Nova Scotia continues to spend money on the Ships Start Here campaign, even though the province's representative in federal cabinet suggests the lobbying effort isn't necessary.

The public relations campaign was launched to help the Irving-owned shipyard in Halifax land a federal shipbuilding contract worth $25 billion.

It's the biggest of two contracts that would mean 30 years of work for the winning shipyard.

About $100,000 was spent on advertising and website development for the Halifax bid, but that was only for the first phase.

Economic and Rural Development Minister Percy Paris won't say how much more the province is spending on advertising in the Globe and Mail and on bus shelters in Ottawa, where the decision-makers live, or how long the campaign will continue.

"I would imagine that we would do it right up until a decision is reached. And once it's over I'm sure that those numbers would be readily available as far as costs are concerned," he said Thursday.

The premier's office says Irving Shipbuilding is splitting the bill and the full cost won't be known until the contract is awarded at the end of September.

The province is refusing to provide an estimate of the Ships Start Here budget.

Peter MacKay, Nova Scotia's representative in federal cabinet, said the whole campaign is unnecessary.

"The decision for two centres of excellence will be made by professional public servants. It will not be affected by politics, political pressure or advertising," MacKay told reporters last week.

But supporters of the Halifax bid aren't taking any chances.

Videos touting "Ships Start Here" are sprouting up on YouTube, and signs dot lawns and businesses around Halifax.

Halifax is competing against shipyards in Quebec and Vancouver. One shipyard is expected to win the big contract for 30 large combat ships for the navy, while a second shipyard would get the smaller $8-billion contract for supply ships and coast guard vessels.

The federal government plans to spend another $2 billion on contracts for small craft and repairs.