CALGARY -- Enbridge Inc. is proposing a series of transactions with its co-investors in four affiliated businesses, who are being offered company shares worth a total of about $11.4 billion based on current stock prices.

If the transactions unfold as anticipated, investors in all the companies and limited partnerships would hold shares in Enbridge, one of North America's largest energy infrastructure companies.

The Calgary-based company said the moves would address risks caused by the loss of a U.S. tax allowance that will affect certain interstate pipelines held within master limited partnerships, or MLPs.

"The combination of this changed policy and the negative capital markets reaction has impaired the MLP structure for Enbridge's interstate pipelines," the company said in a statement.

Enbridge is proposing separate all-share proposals with the boards of Spectra Energy Partners, L.P., Enbridge Energy Partners, L.P. , Enbridge Energy Management, L.L.C. and Enbridge Income Fund Holdings Inc. (ENF)

It said that Spectra Energy Partners and Enbridge Energy Partners face a cessation of distribution growth and a compromised outlook for their unitholders as early as 2019, which will have an impact on the other entities.

The plan, if accepted on the proposed terms, would simplify the Enbridge corporate structure with a neutral impact on its current three-year financial guidance and result in a positive impact after 2020, it said.