Finance Minister Joe Oliver rushed to table tax measures for the Conservative government's second budget bill on Friday after his department accidentally leaked details of the changes online.

A 281-page ways and means motion, an official notice to the House of Commons of government plans to introduce legislation involving tax changes, was tabled on Friday, earlier than the government had planned.

On Thursday afternoon, Mr. Oliver's department accidentally posted a news release with extensive details of tax measures that will appear in the upcoming budget bill.

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Just after 4 p.m. on Thursday afternoon, a news release outlining a range of personal, business and international tax changes was posted on the Finance website for a few minutes before it was taken down.

The error brought questions from the Official Opposition on whether anyone could have profited from it.

"I take this situation very seriously and have instructed the department to review its procedures to ensure it does not happen again," Mr. Oliver said in a statement on Friday evening .

The news release indicates the budget bill will include "income tax and sales tax measures" that were not in the budget. These include changes related to securities rules for foreign affiliates of Canadian banks, new rules for international shipping corporations and improving the operation of the Canadian film or video production tax credit.

The department had apparently intended to post a news release on an enhancement of the Children's Fitness Tax Credit Prime Minister Stephen Harper announced on Thursday. Because the fitness credit announcement involved a tax change, a 12-page ways-and-means motion was tabled in the House of Commons that day.

After the mix-up, the government on Friday tabled the motion "to implement certain provisions of the budget tabled in Parliament on February 11, 2014 and other measures." It outlines the measures in the news release that was posted in error.

Late Friday afternoon, Finance re-posted the news release.

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NDP finance critic Nathan Cullen sent a letter of concern to Mr. Oliver on Friday.

"The leak and availability of this information, prior to it being made public, gave those with this information an opportunity for personal financial gain," the letter states. "This could obviously lead to insider trading and market distortions."

The letter asks the minister to explain how the department is addressing the leak and "whether you have asked appropriate authorities to investigate."

Mr. Oliver's statement makes no mention of an outside review. It confirms that he ordered the information tabled right away: "I also tasked the department to get the ways and means motion prepared for tabling in the House of Commons as quickly as possible after this mistake was discovered. This afternoon, the ways and means was tabled in the House to ensure all Members of Parliament and Canadians had full access to the measures contained within."

Former parliamentary budget officer Kevin Page, who worked on federal budgets at Finance and the Privy Council Office, slammed the government over the incident.

"It's something that just shouldn't happen," Mr. Page said. "Are markets actually going to move? It would depend on the timing of the measures and the market sensitivity of the measures. ... It is still serious from a procedure standpoint. It shouldn't happen. It's very sloppy."

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Parliamentary convention is that ministers table legislation before details are made public. However, Finance sometimes releases legislation in draft form for consultation. Some of the measures in Friday's ways and means motion were previously released this way.

The full budget bill will not be released until at least the week of Oct. 20.