The British Columbia government filed a constitutional lawsuit Tuesday countering an Alberta government bill that would limit fuel being sent to the province.
Horgan said he didn't anticipate any high tension at the conference, even when Notley was still planning to be there, and that he expected the main focus of the meeting to be the development of a national pharmacare program.
Kinder Morgan has ceased all non-essential spending on the $7.4-billion pipeline project that would twin the existing pipeline between Burnaby, B.C., and Edmonton.
Deputy Premier Sarah Hoffman will be attending the conference on Notley's behalf.
Notley bowed out of a Western premier's meeting on Wednesday in Yellowknife, saying she could not discuss issues like a national prescription drug plan in the presence of B.C. Premier John Horgan while his government is trying to stop the pipeline project.
Eby said the lawsuit filed Tuesday in Alberta's Court of Queen's Bench challenges the constitutionality of Alberta's law because it is meant to punish B.C.
Premier Notley initially praised the Horgan move as a step in the right direction ("stepping back from the brink and abiding by the law") and suspended her wine boycott.
"We only have a number of days until the deadline Kinder Morgan has set and so Premier Notley's only priority is ensuring the pipeline gets built", Ms. Oates said.
"We're going to be introducing legislation shortly which will inflict pain on British Columbia", she said in part.
She and other Alberta ministers made similar statements when Bill 12 was introduced, debated and passed, leaving no doubt that "its goal was to authorize the government of Alberta to reduce supplies of crude oil, natural gas and refined fuels to cause economic harm to British Columbians in order to punish and put pressure on B.C".
Alberta sees the pipeline as key to moving bitumen from the province to the west coast and from there to lucrative overseas markets. Indeed, as Bloomberg pointed out at the end of last week, "Justin Trudeau's pipeline nightmare may be only getting started ... the prime minister could end up fighting for an asset that hardly anybody wants".
"We have granted permits at the same pace and with the same process as the previous [B.C.] government", he said Tuesday.
The spill comes less than a week before the company's self-imposed deadline to make a final decision on the Trans Mountain expansion.