OTTAWA — Canada’s highest court on Friday turned aside a challenge by some disgruntled Bell Canada bondholders and paved the way for the $52-billion leveraged buyout of parent company BCE by a consortium led by Teachers’ Private Capital and including several U.S. private equity firms.

Seven judges presiding over the Supreme Court case unanimously overturned a Quebec Court of Appeal decision that sided with the bondholders, who claimed the deal was detrimental to them because Montreal-headquartered BCE was making their investments less valuable by taking on $34 million in debt.

The decision ‘affirms BCE’s long-standing position that the plan of arrangement complies with the rights and reasonable expectations of Bell Canada debenture holders,’ said BCE and Bell Canada chair Richard J.Currie. ‘We expect all parties to the transaction will honour their commitments.’

It is being hailed as a ground-breaking ruling because it enshrines in Canadian law the rights of shareholders as foremost in mergers and acquisitions.

In a statement, the Bell Canada debenture holders said they ‘are disappointed that the court disagreed with them on the merits.’

The legal challenge though has delayed the acquisition, just as the CRTC gave its final approval late Friday, and Industry Canada confirmed it would give the deal the greenlight early this week.

BCE says its objective now is to close the transaction in the third quarter of 2008, instead of the original target of end of the second quarter.

‘We are pleased with the Supreme Court’s decision and are continuing to work to complete an acquisition of BCE,’ said Ontario Teachers’ Pension Plan CEO Jim Leech.

Trouble could still be brewing as the banks that are backing the deal — including Citigroup, Deutsche Bank AG and Royal Bank of Scotland — are reportedly looking to renegotiate a lower per share price than the originally agreed upon $42.75, given the ongoing credit crunch.

‘We continue to negotiate the financing documents in good faith with the sponsors and stand behind our original commitment to the transaction,’ the banks said in a carefully worded statement.

BCE is a 15% shareholder in CTVglobemedia, which controls CTV, its family of specialty channels, and The Globe and Mail.