TransCanada to Acquire Additional Interest in Portland Natural Gas Transmission System

CALGARY, Alberta - October 20, 2003 - (TSX: TRP) (NYSE: TRP) - TransCanada Corporation today announced it has entered into an agreement to acquire El Paso Corporation's (El Paso) 29.64 per cent interest in Portland Natural Gas Transmission System (PNGTS) for approximately US$137.2 million, including assumed debt of approximately US$80.7 million. The closing of the transaction is expected to be completed by the end of this year and is subject to the satisfaction of various closing conditions including the right of first offer provisions.

Under the terms of the PNGTS partnership agreement, the other PNGTS partner, Gaz Métropolitain and Company, Limited Partnership, has the right to acquire its pro rata share of El Paso's offered interest. This right is exercisable for a period of thirty days after receipt of formal notice from El Paso. Should this right of first offer not be exercised, TransCanada' s interest in Portland will increase to 73.06 per cent from 43.42 per cent. Should Gaz Métropolitain's right of first offer be exercised, TransCanada's total interest will increase to 61.71 per cent. The purchase price paid by TransCanada would be reduced proportionately.

"Increasing our interest in PNGTS bolsters TransCanada's role as an energy supplier in the U.S. Northeast," said Hal Kvisle, TransCanada's chief executive officer. "PNGTS is a strategic link in the U.S. Northeast, providing this market access to current and future supplies of natural gas."

PNGTS owns a 471-kilometre (290 mile), 220 million cubic feet per day interstate natural gas pipeline which connects with the Trans Québec & Maritimes Pipeline near Pittsburg, New Hampshire and serves delivery points in Maine, New Hampshire and Massachusetts, including the Boston area. Last month, TransCanada increased its stake in PNGTS by 10.13 per cent by acquiring a portion of DTE East Coast Pipeline Company's interest in PNGTS for approximately US$47.1 million, including assumed debt of approximately US$27.8 million.

TransCanada is a leading North American energy company. We are focused on natural gas transmission and power services with employees who are expert in these businesses. Our network of approximately 38,000 kilometres (24,000 miles) of pipeline transports the majority of Western Canada's natural gas production to the fastest growing markets in Canada and the United States. TransCanada owns, controls or is constructing more than 4,500 megawatts of power - an equal amount of power can meet the needs of about 4.5 million average households. Our common shares trade under the symbol TRP on the Toronto and New York stock exchanges.

FORWARD LOOKING INFORMATION

Certain information in this news release is forward-looking and is subject to important risks and uncertainties. The results or events predicted in this information may differ from actual results or events. Factors which could cause actual results or events to differ materially from current expectations include, among other things, the ability of TransCanada to successfully implement its strategic initiatives and whether such strategic initiatives will yield the expected benefits, the availability and price of energy commodities, regulatory decisions, competitive factors in the pipeline and power industry sectors, and the current economic conditions in North America. For additional information on these and other factors, see the reports filed by TransCanada with Canadian securities regulators and with the United States Securities and Exchange Commission. TransCanada disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

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