The Opposition in Saskatchewan says the province's political donation laws are the weakest in the country and often are described as the Wild West.

There are no donation limits for contributing to registered political parties or candidates in Saskatchewan; however, donations can only be made by Canadian citizens.

The NDP says the Saskatchewan Party has raked in more than $2 million from out-of-province companies, mostly from Alberta.

NDP Leader Trent Wotherspoon says it's time to stop corporate, union and out-of-province donations, and for a cap on individual contributions.

"We believe we should get big money out of Saskatchewan politics, make sure that ultimate trust is there for Saskatchewan people, address questions of influence and I think Saskatchewan people just don't feel it's right to have millions of dollars flowing in, for example, from Alberta corporations," Wotherspoon said Wednesday.

Premier Brad Wall says the Saskatchewan Party has received nearly $30 million in donations over the last decade and about 10 per cent came from corporations with headquarters outside Saskatchewan.

"And we ought not to be surprised by the fact that a lot of companies from outside Saskatchewan in other parts of Canada, not only in Alberta, who are invested here, who are creating and sustaining jobs here, would have a real interest in public policy and, yes, even elections in the province of Saskatchewan," Wall said Wednesday.

Documents on Elections Saskatchewan's website show that the Saskatchewan Party had 1,377 corporate donations in 2015, totalling $1,699,139. It had two donations from trade unions totalling $2,150.

The NDP had 51 corporate donations totalling $144,870.40 last year and $211,156.90 from 55 donations from trade unions.

Jim Farney, a University of Regina political science professor, says the federal government and most other provinces have rules limiting who can donate to a political party.

Federal parties are subject to the most stringent financing rules in the country, with individual donations limited to $1,500 per year and corporate donations banned altogether. That happened 10 years ago.

"That would be kind of the hardest line in the sand," said Farney.

"And the reasoning for that, I think, is kind of two-fold. One is, it's not just that the system has to prevent influence from people buying access or buying influence, but it also has to be seen to do that and the easiest way to do that is to put the rate so low that nobody's special."

Farney says the second reason is to create an even field between political parties.

"You want a system where you don't get widely disproportionate funding for at least the major ones. And putting the individual cap pretty low seems to do that."

The former NDP government in Manitoba banned corporate and union donations and limited individual donations to $3,000 per year.

Corporations and unions are also banned from donating to political parties in Alberta.

Ontario has tabled a bill that would ban corporate and union donations.

Wall says there are no plans to change donation laws in Saskatchewan.

"One of the curious things about the Wall government is that they've never been that interested in that kind of democratic or election reform, generally. We haven't updated the elections act in a serious way since '96," said Farney.

"We haven't looked at campaign finance. We just got a lobbyist registry rolling a couple of months ago. We haven't really looked at third-party donations."