Saskatchewan Premier Lorne Calvert says he has emerged from a federal finance committee meeting in Ottawa wondering if any federal Conservative campaign promises can be trusted.

"What's the fine print?" he said to CBC News following a testy exchange with Conservative MPs while discussing equalization.

Calvert has joined Newfoundland and Labrador Premier Danny Williams in harshly criticizing the federal budget for its changes to the equalization program.

The federal Conservatives lived up to a campaign promise to exempt non-renewable resources from the equalization formula, with one major change — they introduced a cap on equalization payments to provinces that make money from oil and gas.

As a result, instead of getting what Calvert said should have been $800 million a year, Saskatchewan gets $226 million this year and nothing next year.

The fact that there was no mention of a cap during the election campaign means the budget measure was a broken promise, Calvert said.

Calvert sparred verbally with Saskatchewan Conservative MP Gerry Ritz over the issue. Calvert said later he was particularly irked by comments from Calgary Conservative MP Diane Ablonczy.

"You say there was no mention of a cap when this was discussed in election rhetoric, but there was no mention that there would not be a cap, either," Ablonczy said in the committee meeting.

Calvert said Ablonczy's comment was disturbing and raises more questions about whether the federal government can be trusted when it makes promises.

Equalization is the federal program through which Ottawa makes payments to so-called have-not provinces so they can offer the same services and tax rates as more well-to-do provinces. Saskatchewan has been enjoying an oil boom in recent years and its equalization payments have been slashed.

The Conservatives have countered critics by saying Saskatchewan has done well in terms of transfer payments from Ottawa since the Harper government came to power.

In a press release last week, Saskatoon-Rosetown-Biggar Conservative MP Carol Skelton said the budget gave Saskatchewan almost $900 million in new money.

Per capita, that's more than any other province received, she said.

The federal Liberals say that's just money Saskatchewan would have received anyway.