Just over a year after the last general election, the Conservatives have plunged the UK into chaos with David Cameron gambled with the country on Brexit, and now a Tory leadership election has turned into a coronation.

It is simply inconceivable that Theresa May should be crowned prime minister without even having won an election in her own party, let alone the country. I believe there must be a general election. I thought it when Gordon Brown became prime minister and I think it now. The Conservatives must not be allowed to ignore the electorate, particularly now their mandate is shattered and whatever programme May offers can’t look like the platform she stood on in 2015.

Britain needs a strong, united and effective opposition and I believe the Liberal Democrats can provide it.

In an early election the Liberal Democrats will set out an optimistic, positive plan for Britain. We will stabilise the economy, improve education, deliver a new deal for our NHS, restore the green agenda, and secure Britain’s place at the heart of Europe.

The Fixed Term Parliaments Act contains provisions to dissolve parliament early

Theresa May should show leadership and tell the Queen when she visits Buckingham Palace this week that there will be an election in due course. Because the case for an early election is overwhelming.

Some people have raised the Fixed Term Parliaments Act as an obstacle to an election, but I don’t buy that argument.

The act wasn’t intended to allow the undemocratic appointment of a new prime minister, which is exactly why it contains provisions to dissolve parliament early. If May is canny, she will want to call one to secure her own mandate – not least because Labour is providing no credible opposition at all. The party’s obsession with its own divisions has allowed the Conservatives to go unchallenged. It is telling that Jeremy Corbyn has been utterly silent on the subject of an early election, despite the fact it is what the country needs.

If May wants a general election, the Fixed Term Parliament Act allows her to put a motion to parliament calling for one, which would require the backing of two-thirds of MPs for it to succeed. Liberal Democrats would back such a motion – the question is whether Labour and the SNP will join us in doing so.

The Conservatives’ record in government over the past 12 months, without the Liberal Democrats, has been poor. The economy has weakened due to the massive constraints placed upon it by the conspicuously absent chancellor, and the stability they promised, now so desperately needed, has not been delivered.

Just 0.0003% of people in the UK have backed May as their new prime minister. That’s the 199 MPs who voted for her over her leadership rivals. The person that triggers Article 50, which leads us out of Europe, has to have a clear direction from the country, even if under our outdated and inadequate first past the post system that may be difficult to achieve.

The United Kingdom is now in uncharted waters. We face big decisions on how Brexit should look, on Tata steel, on the economy, our public services and foreign conflicts like Syria and Libya. We cannot anoint someone who has not explained their position on any of these – saying “Brexit means Brexit” is not a plan, it is a vacuous phrase.

I urge Theresa May to recognise that, and to put the interests of the people first, ensuring that the next government has a democratic mandate.

In 2007, the then opposition leader David Cameron demanded Gordon Brown take his premiership to a vote; “Gordon Brown doesn’t have the mandate, he wasn’t elected as prime minister, and he should go to the country.” May herself ridiculed Brown for “running scared”. As someone who campaigned alongside me for remain, but must now deal with the consequences of leave, May should appreciate that there is at least as much at risk today as there was nine years ago.

We should not let fears of election fatigue prevent us from arguing what is in the best interests of the country. In 2015, just 36.9% of people elected the government of today, a government that took us into the referendum, and out of Europe. With the recent campaign having caused so much bitterness, the electorate needs its politicians to give them the opportunity to elect a government that will work towards eliminating the divisions that have been revealed and reinforced.

British politics is in turmoil. Our country risks fragmentation, and those of us who believe in the United Kingdom should do everything we can to avert this course.

May has the power to bring a motion to parliament requesting an early election, and to present her vision of the Britain’s future to the 40 million or so people who make up our country’s electorate.

That is certainly more just than leaving it in the hands of less than two-thirds of the Tory MPs sitting in the Palace of Westminster.