Later today, I will get off a train in Cardiff and I won't feel like I'm in a foreign country.

One of the great things about the UK is the diversity of the nations we have within our borders. But from the Highlands of Scotland to the valleys of Wales, every bit of my experience tells me that we are more alike than we are different.

There is a reason why the four nations that make up the UK are called the home nations.

With 90 days to go until the referendum, it is a good time to think about what exactly we will be leaving behind if we were to say goodbye to the United Kingdom on September 18.

Over the coming months the Nationalists are going to try to make the argument that we can cut all ties with the UK, but still so much will remain the same. We need to be honest about what separation means. It's not just separating ourselves from the Tories, as Alex Salmond wants us to believe. It's separating ourselves from people we have built alliances with in Cardiff, Liverpool, Manchester and Newcastle.

And the truth is that most people in Scotland want our political partnership to continue; not just in terms of remaining part of the United Kingdom.

They want to continue to work with our friends and allies in places such as Wales. And they want the rights and entitlements across the UK to remain the same.

Recent independent research has shown that a majority of Scots want pensions and benefits to be the same across the UK.

And they want our resources, including our oil wealth, to be pooled and shared with people across the country because it works to our shared benefit.

This doesn't surprise me. Scotland has always had its own distinctive identity and we have developed our own agenda. But we also want to work across the UK when we have shared interests and shared priorities.

That is why this evening at the National Assembly for Wales, I'll be making the case for continuing to work together, and for continuing with devolution, which maintains strong national parliaments at the same time as it keeps the political framework that allows us to work together.

A year from now, if Scotland votes No and I am Secretary of State for Scotland, my priority will be making sure that we work together across the UK to continue to make devolution a success.

And the next Labour Government will be in the best position to make that happen.

Not only do we have two leaders in Johann Lamont and Ed Miliband who are committed to further devolution; but we also have a new generation of politicians for whom devolution is the norm.

This is Labour's Devolution Generation - politicians with a deep understanding of devolution and, in my case, with several years of experience serving in the Scottish Government.

It is because of the guarantees we have offered and the political will behind them that people across Scotland should have no doubt that a No vote in September means more powers for Holyrood.

However, we need to go further than simply passing powers from London to Holyrood, or to Cardiff Bay.

With so many significant challenges facing all the nations of the UK, from rebuilding our economy to tackling the cost of living crisis, we need all the governments that serve our people to be firing on all cylinders to tackle the day-to-day problems people are facing.

People should rightly expect nothing less from us. That is why, this evening in Cardiff, I'll be setting out some of our thinking about how we strengthen the UK.

As we have said many times, Scotland can have the best of both worlds: a strong Scottish Parliament inside the UK.

And, as we move forward over the coming months, with the guarantee of further powers backing us up, Labour will be making even clearer how we will set out to change the whole of the UK.