British Prime Minister Theresa May is seeking to reassure European Union leaders that her Brexit timetable remains intact despite an adverse court ruling.
She plans to telephone European Commission President Jean-Claude Juncker Friday to spread the word that her plan is still to start the process to remove Britain from the EU by the end of March.
May's ability to invoke Article 50 to formally begin the process may be slowed, however, by a High Court ruling that the government needs Parliament's approval first.
The Government plans to appeal this ruling to the Supreme Court with a hearing expected next month. If the country's highest court rules against the government, Parliament will become directly involved in the Brexit situation.
The prospect of parliamentary involvement has raised the prospect of delays in the Brexit process and also the possibility of an early general election in Britain.
The court decision is the first significant setback for May's Brexit plan, which calls for Article 50 to be triggered early next year, leading to an expected two years of negotiations between Britain and the EU.
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 favour of exiting the 28-nation EU bloc.
THE GOVERNMENT WINS THE NEXT ROUND
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.
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 favour 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 favour of Article 50.
Parliament would face overwhelming political pressure to respect the will of the people as expressed in the referendum, where 52 per cent 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 favouring a "soft" Brexit that emphasises 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 prioritise 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.
GOVERNMENT COULD 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 favour 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.