Yesterday I wrote to you about why we have to take difficult decisions to tackle the deficit and lay the foundations of a fairer society. These are not decisions that any government wants to take but we have no choice except to clear up the financial mess that Labour left us. Today’s Budget takes these difficult decisions in an honest and fair way and with the clear stamp of Liberal Democrat values running through it.

In the past, efforts to tackle a big deficit have always hit the poorest the most. The coalition has ensured that – for the first time – this will not happen. The richest will pay the most, while pensioners and children will be protected.

Look through the Budget and you will see key policies we campaigned for being put into effect.

Tomorrow, the coalition government will deliver an emergency budget to bring order back to the public finances. It will be a difficult budget - but remember, as you hear it, why we have to do this.

Labour left our country with a mountain of debt. Every minute that goes by the government spends a staggering £80,000 on interest, that's over £800 million a week. If we don't take action now, the markets will force us into even more drastic measures as they have in Greece and Spain.

Without action on the deficit, we will carry on racking up unaffordable debts our children will have to pay off. We will carry on spending more money on debt interest than we do on our schools. And we will undermine the economic growth needed to create jobs and opportunities for all of us. There is nothing fair, liberal or progressive about any of that.

Of course, the Labour party will say that these decisions are not justified. They will say the budget creates risks for our economy and that Liberal Democrats have sold out to go along with Conservative cuts. They are wrong.

Every time you hear Labour say that, ask them why they covered up the details of the £44bn of cuts they themselves had planned. Ask them why they racked up so much debt that we could end up spending £70bn a year just on debt interest. And ask them why they created this fiscal bombshell in the first place by refusing to take action against the reckless banks even when Vince Cable warned of the risks they were taking.

Until Labour accepts the blame for the mess we are in and comes up with a plan for getting us out, they cannot be taken seriously.

We have always argued that cuts would be necessary, but the timing should be based on economic circumstances, not political dogma. The economic situation today means that time has come.

A lot has changed even in the last few months. The crisis in the Eurozone and the problems in Greece and Spain have put huge pressure on us. The new Office of Budget Responsibility has shown that the structural deficit is bigger than we thought. And in government, we have discovered billions of pounds of unfunded spending promises Labour had made, cynically raising people's hopes when they knew the coffers were bare.

So cuts must come. We have taken the difficult decisions with care, and with fairness at their heart. You will see the stamp of our Liberal Democrat values in tomorrow's Budget. But nonetheless, it will be controversial. This is one of the hardest things we will ever have to do, but I assure you, the alternative is worse: rising debts, higher interest rates, less growth and fewer opportunities.

This morning, the Office for Budget Responsibility – an office established by this Government – published its first assessment of the public finances. Regrettably the problems facing our country are even more serious than we had originally realised.

We and many others have been warning for some time that the growth forecast in the March Budget was optimistic. The Office for Budget Responsibility confirms this. And because trend growth is lower than expected, the structural deficit is larger than anyone realised. In 2010/11 it’s going to be 8% of GDP – that’s £118bn; £11 billion more than Labour told us, rising to £13 billion next year. So the scale of the problem is even bigger than we thought.

The OBR’s independent analysis paints a stark picture. We are now facing the highest budget deficit in Europe, the highest deficit in the G20. Government borrowing this year will be ten and a half per cent of GDP, with debt topping 60%. As we always suspected, and as confirmed by this report, the downturn did more damage to the economy than Labour admitted. This is the reality that confronts us.

Labour’s approach is clear: deny the problem, play games with the numbers, and promise money we don’t have.

We have always said that we would not shrink from this task. There are tough choices to be made, but we will make them now while we can do so in a way that is both fair and just. This government, Liberal Democrats and Conservatives together, will see through the deficit reduction that is an absolute prerequisite for turning Britain’s fortunes around.

Make no mistake: this is not a task we relish. Nor was it our choice. This is the legacy that we, as a new government, and we, the British people, were left. It is the only way we can get our public finances on a sound footing. To do anything else would not only be irresponsible; it would be a betrayal of our progressive values. There is nothing progressive about denial. And there is nothing progressive about condemning ourselves and our children to decades of debt, higher interest rates and fewer jobs.