'It brings certainty and that by any measure is a great result,' a top UK automotive executive said, declining to be named.
On Friday, the SMMT car makers' association said the UK government's priority now must be to restore business and economic confidence and re-establish the UK's reputation as a great place to invest at a critical time for the industry.
'When automotive succeeds so does Britain. We look to the new government to maintain our global competitiveness, which means delivering a deal with the EU that is ambitious, maintains free and frictionless trade, and drives growth and innovation to meet shared environmental goals,' SMMT CEO Mike Hawes said in a statement.
Car makers have warned that if Britain's exit from the EU leads to tariffs, UK-built autos would be uncompetitive when sold in mainland Europe.
British factories would also be hit if imports of parts from suppliers in mainland Europe are delayed at borders. UK car factories are integrated into supply chains that can stretch around the world and operate just-in-time manufacturing processes. This mean some parts arrive minutes before being fitted onto vehicles rolling off production lines.
Johnson's victory gives him the power to get his own way on Brexit, especially if he needs extra time to negotiate with the EU. He has said he will start to push legislation through parliament before the end of the year to meet the current departure date of 31 January 2019.
However, if Britain wants access to the bloc's single market, it will have to give up control in some areas, in particular taxation, labour and environmental standards. Hard-liners in the Conservative party are likely to object to that and push for a clean break from the EU at the end of the year. But Johnson's big majority could allow him to marginalise them and cut a deal that keeps the UK more closely aligned with the EU.
Nissan Europe Chairman Gianluca de Ficchy has said that if a hard Brexit leads to tariffs of 10% between the UK and EU, the future of the car maker's Sunderland factory in northeast England would be in doubt. 'If it means the implementation of World Trade Organization tariffs of 10%, the overall business equation is not sustainable for us because 70% of our vehicles are exported to Europe,' he told Automotive News Europe in a recent interview.
A Nissan spokesperson said on Friday that the company looks forward to meeting the new government to ensure that the car makers Sunderland plant, continues as a successful international automotive hub.
Jaguar Land Rover CEO Ralf Speth has said that the' wrong' Brexit deal would cost the UK car industry tens of thousands of jobs. JLR has three car UK plants from which it exports cars worldwide.
Toyota has warned that it may end manufacturing in the UK if the country crashes out of the EU on unfavourable terms. Toyota built just over 8% of Britain's 1.52m cars last year at its factory in Burnaston, central England.
Here are the next steps for Johnson.
Pass the withdrawal bill
Lawmakers return to Parliament on 17 December 2019 and Johnson will want to move rapidly to enact the Withdrawal Agreement Bill. This is the formal legislation taking Britain out of the EU. First, though, he will have to pass a Queen's Speech proving he has the confidence of the House of Commons so the Brexit law may have to wait until the new year.
Johnson will need to steer the legislation through parliament before 31 January 2020, otherwise Britain would crash out of the EU without an agreement. Then the country will enter a transition period, during which time almost all EU rules will continue to apply.
'We expect as soon as possible the vote by the British parliament on the withdrawal agreement,' European Council President Charles Michel said on Friday in Brussels. 'It's important to have the clarity as soon as possible.'
Negotiate trade deal
Johnson's focus will then turn to negotiating a new trade relationship with the EU. He will be working against the clock, having 11 months to negotiate a comprehensive free trade agreement, a process which normally takes several years.
First, he will need to hold a parliamentary vote on his negotiating objectives. He may face pressure here from the hard-liners in his own party, who yearn for the freedom to diverge from EU standards. Then he will need to appoint a negotiating team.
The EU will also need to agree on its negotiating mandate before talks start. Getting these approvals will eat into the transition period.
The contradiction Johnson will have to resolve in trade is his desire for both autonomy from EU rules and access to the single market. The EU has indicated it is willing to give Britain a zero-tariff, zero-quota deal as long as the UK does not become a lightly regulated 'Singapore-on-Thames.'
The UK and the EU have until 1 July 2020 to decide whether to extend the transition period by up to a further two years, if both sides need more time for negotiations.
The Conservatives ruled out extending the transition in their manifesto even though trade experts say completing a comprehensive agreement by the end of 2020 is highly unlikely. That leaves open the risk that Britain could still leave without a trade agreement in place. But, with his majority, Johnson could just decide to extend the transition period.
Continue trade negotiations
If the transition is not extended, the UK and the EU will face an intense six months to finalise a deal. The danger for Johnson in this period is that he will come under pressure to cede to the EU's demands in areas such as fishing and food standards to avoid crashing out without a deal, Ivan Rogers, the UK's former ambassador to the EU, warned in a lecture in November.
The House of Commons will have to approve the future relationship agreement. Each of the EU's 27 national parliaments as well the EU Parliament itself will have to ratify it, too.
Start new relationship
The first day of 1 January 2021 should mark the start of the UK's relationship with the EU. Either a future relationship deal will be in place or the UK will default to trading with the EU on basic World Trade Organisation terms. This would look much like a no-deal Brexit.
For Johnson, the risk is this timetable slips allowing Brexit to go on sucking the oxygen out of political debate. His bet is that the logistics of negotiating a trade deal prove far less controversial than the act of leaving itself.
Bloomberg contributed to this report