Media gather outside the High Court in London, Thursday Nov. 3, 2016 as they wait for the decision on the challenge to plans for Brexit. In a major blow for Britain's government, the High Court ruled Thursday that the prime minister can't trigger the U.K.'s exit from the European Union without approval from Parliament. (AP Photo/Tim Ireland)
LONDON (AP) — A High Court ruling that Britain's Parliament must give approval before Prime Minister Theresa May triggers the formal process of taking Britain out of the European Union has cast some uncertainty over Brexit.
Here is a look at the various scenarios that could unfold in the coming months as Britain moves to implement the result of the June 23 referendum vote in favor of exiting the 28-nation EU bloc.
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THE GOVERNMENT WINS THE NEXT ROUND. PROBLEM SOLVED.
The British government is appealing the court ruling to the Supreme Court. The case is likely to be expedited and is expected to be heard, and possibly decided, in December. If the High Court ruling is overturned, the prime minister would be able to invoke Article 50 of the EU treaty, the formal move that begins the exit process, at a time of her choosing. She has pledged to do so by the end of March. Once the starting bell is rung, it is expected the delicate negotiations will take two years to complete, with an extension possible if all members agree.
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THE GOVERNMENT LOSES AND PARLIAMENTARY DEBATE BEGINS
If the Supreme Court lets the court ruling stand, the prime minister would have no choice but to seek a vote in Parliament in favor of starting the Article 50 process to leave the EU.
She says this would not slow her timetable of starting the procedure by the end of March, but it is entirely possible that Parliament would take longer to debate the pros and cons of Brexit and to prepare a bill in favor of Article 50. Parliament would face overwhelming political pressure to respect the will of the people as expressed in the referendum, where 52 percent backed Brexit, but many individual legislators remain opposed while others have indicated that they won't give their backing without certain concessions. That may slow the whole Brexit process.
Parliament may seek to impose conditions on the terms of Brexit, for example favoring a 'soft' Brexit that emphasizes the need to keep Britain in the single market rather than the 'hard' Brexit May has indicated her preference for. In a speech last month, May appeared to prioritize controls on immigration over remaining in the single market.
Once Parliament is involved, the diverse interests and constituencies of the 650 members of the House of Commons will come into play. There are also issues surrounding the House of Lords, Parliament's second chamber which has a revising role. It is difficult to predict what Parliament will do, though most observers feel it is very unlikely its members would feel free to ignore the referendum results and actually vote against the triggering of Article 50.
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THE GOVERNMENT COULD CALL A SNAP GENERAL ELECTION
Some high-ranking Conservative Party figures are urging the prime minister to seek a snap election to bolster the party's position in Parliament ahead of any Brexit vote. The Conservatives hold a slender majority in Parliament that might be significantly increased if a new vote is held.
The opposition Labour Party is in disarray and its leader Jeremy Corbyn does not enjoy strong support from his party's legislators. A successful election could strengthen May's hand and give her more ability to shape parliamentary debate over Brexit.
The next scheduled election is set for 2020 and May would need a two-thirds vote in the House of Commons in favor of a snap election that could be held early next year. She has in the past said a new election is not needed but her view of the situation may change, particularly if the Supreme Court agrees that Parliament must have a vote before Article 50 is put into action.