WINNIPEG -- The Manitoba government examined "different scenarios" before settling on a one per cent increase to the provincial sales tax in the last provincial budget, although those options are being kept under wraps.

The government has come under fire for raising the tax to eight per cent from seven last July and bypassing a referendum required for such a hike under the balanced budget law.

The Canadian Press recently filed a freedom of information request seeking any documents that might show whether the government looked at a steeper increase -- specifically, to nine per cent -- in the three months prior to the budget.

In response, the Finance Department said it was refusing to release some documents under a section of the freedom of information law that exempts advice to cabinet.

"After reviewing the records, we have found that no such record exists. Finance did determine that some preliminary pre-budget analysis on the one per cent increase to PST included two small portions where comparators were developed to provide context to other analysis," the letter states.

"The disclosure of these records is refused as Finance is prohibited ... from releasing records that are prepared for cabinet."

The department's access co-ordinator refused to elaborate, and would not clarify when asked whether the documents included any specific reference to a nine per cent sales tax.

Stan Struthers, finance minister at the time, was not available for an interview. Sally Housser, press secretary to current Finance Minister Jennifer Howard, issued a brief written statement that did not address the question of what specific options the government considered.

"During the budget process different scenarios are put forward, analysed and submitted to cabinet to provide comparisons and context which help inform any potential budget decisions," Housser wrote in an email.

Before he was removed from the finance portfolio in a cabinet shuffle last fall, Struthers said the government never examined any potential sales tax rate higher than eight per cent. Eight per cent was all that was needed for the province to take part in federal infrastructure programs in the coming years, he said at the time.

The NDP government has started preparing its next budget, and Premier Greg Selinger said recently he has no plans for any major tax increases this year.

The government's long-term budget plan calls for revenues to climb by $340 million in the coming year -- an amount that can include economic growth, higher taxes or user fees, Crown corporation profits, or other items.