Premier John Horgan announced Thursday his government is preparing a constitutional reference case to demonstrate its right to impose new restrictions on the transport of Alberta crude oil.

Alberta Premier Rachel Notley responded quickly, saying sa国际传媒淏.C. blinkedsa国际传媒� on something it does not have a right to do, and announced from Edmonton that her governmentsa国际传媒檚 boycott of B.C. wine sales is being dropped.

Notley kept open the possibility that the wine ban could return if B.C. continues with what she says is an illegal effort to dictate what can flow through an inter-provincial pipeline.

B.C.sa国际传媒檚 legal case will take several weeks to prepare, but Horgan said itsa国际传媒檚 not a retreat from the move that enraged Notley and prompted her to bar the import of B.C. wine.

Horgan said the federal government refused his request to join with B.C. to clarify in court his intent to consult on new regulations regarding the Trans Mountain pipeline expansion project. B.C. will proceed on its own.

Horgan said the first four points of the governmentsa国际传媒檚 plan will proceed as announced sa国际传媒� consultation with B.C. residents on oil spill response time, geographic response plans, compensation for loss of public and cultural use of land and the application of regulation to marine spills.

The fifth point, proposed regulation of additional bitumen flows through B.C., sa国际传媒渉as generated disproportionate and unlawful reactions from the government of Alberta,sa国际传媒� Horgan told a news conference at the B.C. legislature.

Horgan said the court action is intended to sa国际传媒渉ave cooler heads prevailsa国际传媒� in the pipeline dispute. He declined to provide any details on the question to be put to the courts, saying B.C. will retain legal experts to develop its reference case.

In addition to barring shipments of B.C. wine into Alberta, Notley has conducted a media campaign calling on Prime Minister Justin Trudeau to enforce the permits his government issued. In a series of newspaper ads placed this week, Alberta echoed Trudeausa国际传媒檚 comments accusing B.C. of putting his national greenhouse gas reduction deal in jeopardy by trying to block a key concession to Alberta.

B.C. has launched the first-ever formal complaint under Canadasa国际传媒檚 inter-provincial free trade agreement to call for the B.C. wine ban to be struck down. The B.C. Wine Institute is also applying to the courts for an injunction against Albertasa国际传媒檚 action.

The Trans Mountain pipeline has delivered crude oil and refined fuels from northern Alberta to Westridge Marine Terminal in Burnaby since 1954, and has been shipping diluted bitumen intermittently since the product became available from the Alberta oil sands in the late 1980s.

The pipeline owner Kinder Morgan Canada has received federal and provincial permits to proceed with twinning the line, a project the B.C. NDP promised to oppose in last yearsa国际传媒檚 election.

B.C. has already filed an application to appeal a B.C. Supreme Court ruling against the City of Burnaby, which tried to use its bylaws to prevent work near the terminal. The National Energy Board recently issued permits to Kinder Morgan for a tunnel through Burnaby Mountain to keep a section of the pipeline expansion away from populated areas.