Coming straight off the back of the Brecon and Radnorshire campaign, we launched our election campaign for Sheffield Hallam at the weekend, with more than 100 people who joined us to knock on doors, deliver leaflets, and help with clerical work in the office.

It seems like promising Lib Dem by-elections are like buses - you wait for a long time and then two come along at once!

In just eleven weeks, however, our country faces an immediate crisis: crashing out of the EU without any deal. The most cavalier and catastrophic of Brexits: putting at risk hundreds of thousands of jobs , public services including our NHS , and even our national security.

So in this moment of national emergency, I stand ready to work with anyone to stop Boris Johnson and his hard-line Brexit government.

Our party is going from strength to strength.

We now have more than 116,000 members, as well as almost 15,000 registered supporters.

Our team in the House of Commons is growing too. A little over a week ago, we welcomed Jane Dodds as our newest MP.

Today, we welcome another addition to our team. Dr Sarah Wollaston.

After very careful thought, I have come to the conclusion that I can best serve the interests of my constituents by joining the Liberal Democrats.

Brexit has not only sucked all the political oxygen from government over the past three years, but it has also consumed the funding and energy that should have been invested in local communities, tackling climate change and supporting the workforce and infrastructure of our NHS, schools and transport.

I can think of about 350 million reasons why a promise from Boris Johnson isn't worth the paper (or bus) it's written on.

The Government promised that the rights of EU citizens wouldn't change after Brexit. So did Vote Leave - many of whose senior figures are now Government officials.

But now we're hearing that if Brexit happens, the Government plans to make EU citizens pay to use the NHS.