NDP critics Peter Julian and Hélène Leblanc added their voices Monday to those objecting to the Harper government's "secretive handling" of foreign investment reviews.

Yesterday, NDP leader Thomas Mulcair denounced the federal government's lack of transparency in its decision to reject a $6-billion bid by Malaysia's state-owned oil company Petronas for Calgary-based Progress Energy Resources during a speech to party faithful in Ottawa.

Mulcair said the decision by Industry Minister Christian Paradis came like a thief in the night.

"The lack of transparency is starting to reach new heights. Who releases such an important decision at midnight on a Friday? Someone who has something to hide and no way to explain," Mulcair said.

In a written statement issued Friday night, Paradis said "I can confirm that I have sent a notice letter to Petronas indicating that I am not satisfied that the proposed investment is likely to be of net benefit to Canada."

Paradis gave Petronas 30 days to convince him otherwise but offered no other details citing confidentiality provisions in the Act.

Progress Energy CEO Michael Culbert said the company "will be working over the next 30 days to determine the nature of the issues and the potential remedies."

"The long-term health of the natural gas industry in Canada and the development of a new [liquified natural gas] export industry are dependent on international investments," Culbert said

In his speech Mulcair said Ottawa's lack of transparency was bad for business and the economy.

"In the absence of a transparent and open process, investors can't be certain these decisions aren't made for political reasons or influenced by pure cronyism, said Mulcair adding that Canadians also "can't be certain that the development of our strategic resources will benefit Canada."

Nexen takeover review extended

Paradis recently extended the federal government's review of China National Offshore Oil Corp.'s (CNOOC) $15 billion proposed takeover of Calgary's base Nexen Inc. under the Investment Canada Act by 30 days.

The Act provides for an initial 45 day review with the possibility of a 30-day extension.

While shareholders have already signed off on the deal, any proposed foreign investment bid worth more than $331 million requires regulatory approval from the Canadian government.

Paradis said "the review period may be extended again, with the consent of the investor. A decision can be made at any time within this period."

The NDP has come out swinging against this deal citing national security and environmental concerns.

Mulcair told party brass, "the proposed takeover of Nexen by CNOOC, based on the available information, is not to the net benefit of Canada and we call on Conservatives to reject that deal."

The NDP is also calling on the Conservatives to amend the Investment Canada Act and better define what "net benefit" means.

But Conservatives have repeatedly said this transaction, like all others, will be assessed on six factors as outlined in the Act, including whether or not it is of "net benefit" to Canada.

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