The first hurdle that Mrs May must overcome, however, is the Fixed Term Parliaments Act 2011.  This has made it harder for governments to call snap elections by removing the prerogative power of the Queen to dissolve Parliament at the advice of the Prime Minister.  Instead, under the 2011 Act, General Elections may only take place every five years or alternatively where the House Commons either (a) votes by at least two-thirds for an early General Election, or (b) passes a motion of no confidence in the Government and no alternative government is confirmed within 14 days.  This may prove to be a technicality: the initial reactions from representatives of the Labour Party and Liberal Democrats, who have both welcomed the challenge, suggest that Mrs May will easily reach the two-thirds majority in the House of Commons when the vote – expected tomorrow – is held.

How will this affect the Article 50 process?  The March 2019 deadline remains, but there is a possibility that the UK will be constrained and distracted in its engagement with the EU27 until after the election.  This may not materially affect the timetable for the negotiations in the short term.  The European Council must first agree on the EU's negotiating position, which will necessarily happen without the UK being present and which is expected to be finalised at a summit scheduled for 29 April.  Following that, the French and German Presidential Elections, in May and September respectively, had previously led some to believe that the substance of the Brexit negotiations may not get underway in earnest until autumn in any event.  If so, a General Election in the UK could have a negligible impact on the negotiation timetable if Mrs May goes on to achieve a majority, as she hopes and the most recent polls suggest.

The election will impact on the UK Government's domestic policy, including in relation to Brexit. Parliament will be dissolved on 3 May. During the General Election campaign period, government activity is also restricted to non-policy related administrative activities only.  As a result, it is now highly likely that the UK Government will push back the publication of the Great Repeal Bill, which was expected soon after the Queen's speech in May, as well as other major policy initiatives, such as a post-Brexit immigration Bill. 

Assuming the General Election goes ahead, it is likely to be more challenging for businesses to engage with the UK Government on Brexit in the coming weeks.  However, in the event of a clear majority for the Conservative Party in June, this would be a significant opportunity for businesses to reengage with a new post-election government with a clear mandate and fresh impetus to see through the negotiation process.  Doing so quickly and in an effective and targeted manner has the potential to influence the UK Government's direction of travel in a number of policy areas for the foreseeable future.