The biggest contribution we can make to international solidarity is to change things in our own country, which is still one of the world's centres of imperialism. Our own people are suffering too.

The ruling class in Britain, with the City of London finance capitalists at its core, has used the economic and financial crisis to escalate its offensive against workers and their families.

The new Labour government of Gordon Brown and Alistair Darling rescued the banking sector and the whole British economy, with a bailout that now amounts to £1.3 trillion in buyouts, loans, guarantees and "quantitative easing."

This blood transfusion for British capitalism far exceeds any subsidies received by the old nationalised industries. And is British big business grateful to Labour for rescuing it once again, as it did in the post-war reconstruction period after 1945?

Of course not. Once Labour has served its purposes, state-monopoly capitalism and its mass media want Labour out, and the Tory first 11 back in office to turn the screw even tighter.

And the Tories, the Daily Mail, the Sun and the rest of the pack are only emboldened by Ed Miliband's timidity and Ed Balls's gabbling cowardice.

But faced with the rampant fraud, greed and crookery of the City of London Britain's communists say - nationalise the banking sector, don't subsidise it.

Shut down the tax havens under British jurisdiction around the world.

When top company executives in Britain grab 143 times the average wage of their employees - three times the gap in the 1990s - slap a wealth tax on the super-rich.

If Labour is serious about winning the general election next May, the party should adopt these and other popular policies that would inspire millions of electors and throw Ukip into retreat.

Does anyone now argue that taking the railways, Royal Mail, gas, water and electricity back into public ownership would be anything but a vote-winner?

Ah, the still lurking new Labourites say, that's all very well but how could we possibly afford it?

Well, I went to the FTSE 350 index and costed a shopping list based on the market value of all the shares in the following companies:

n Centrica & British Gas £14.8 billion

n Scottish & Southern Electric £15.1bn

They account for almost 50 per cent of the domestic energy market. We could throw in all the infrastructure and buy the national grid for £35.3bn.

This would be by far the best basis on which to plan the vital switch to guaranteed investment in renewable wind, tidal, geothermal and solar power and the development of nuclear fusion and thorium technology within the public sector.

The Tory government's alternative - huge subsidies and guaranteed corporate profits for fracking and nuclear fission - is a ticking financial and environmental time bomb for which future generations will not thank us.

To carry on with the shopping:

n Pennon Water £3.4 bn

n Severn Trent £4.7bn

n United Utilities £5.9bn

The water companies owned by French, Australian and Middle Eastern interests would add another £20bn or so to the bill.

Bringing the Royal Mail back into public ownership, but with a more democratic model which involves the workforce and their union in decision-making, would cost £4.7bn at Thursday's share price.

The privatised railway franchises could be taken over for nothing on expiry, although a Labour government could buy them out early for around £25bn.

Ten-year Treasury bonds could pay the dispossessed owners £2.5bn a year in interest, instead of the same amount that we currently hand them every year in state subsidies for nothing in return.

The £28bn in state funds earmarked for infrastructure investment through National Rail would then go into an efficient publicly owned industry, rather than into a high-fare profiteering private one.

And while we're shopping in the transport department, we could pick up the First Group for £1.5bn, National Express for £1.2bn, Go-Ahead for £1bn and - without the enthusiastic support of the SNP - Stagecoach for £2.1bn.

Successive British governments guarantee huge profits for the armaments industry, parts of which could be converted to more socially useful production.

One of the biggest companies, BAE Systems, would cost £14.5bn.

Qinetiq, the company set up by new Labour to promote arms conversion but which used military technology to boost corporate profits before being privatised, could be had for £1.3bn.

Finally, although taxpayers have already paid for the main British banks several times over, we could buy out the remaining shareholders of Lloyd's and RBS for around £57bn and snap up Barclays for £37.7bn and HSBC for £121.5bn.

How much is that at the till? Presuming that all the shares are being bought, and not just a controlling parcel, and that the prospect of nationalisation has not driven down their value, the bill would amount to just under £370bn.

Where would the money come from? If we wanted to buy each company outright, the Brown and Cameron governments have had no problem finding £375bn in the Bank of England to fund the banks through quantitative easing.

So we would even have some change from that. Or the government could finance the annual interest payable on Treasury stock, issued in place of existing shareholdings, out of the annual profits or state subsidies that these companies enjoy.

All of which begs the question - what kind of government would take such bold steps to secure, modernise and plan key sectors of Britain's economy?

Together with the Morning Star, our party has worked hard to stimulate and guide discussion in the labour movement about the crisis of working-class political representation in Britain.

The crisis must be resolved in the interests of workers and their families in England, Scotland and Wales - not on the basis of any type of nationalism but on the basis of class politics, uniting the working class not dividing it along national or ethnic lines.

Developing policy for progressive federalism, including devolution for England, is an urgent and important task that this congress can perform for the labour movement.

The period up to, during and immediately after the general election is likely to prove decisive in helping us to assess whether the labour movement can and will reclaim the Labour Party or whether major sections of the movement will have to consider what steps should be taken to re-establish a mass party of labour, one capable of winning general elections, forming a government and enacting far-reaching reforms in the interests of the working class.

In order to create the most favourable conditions for resolving this question, and to advance the immediate interests of working-class people, an upsurge is needed in mass activity and action.

That is why it's so important that we discuss the priorities and line of march of the trade union movement, the People's Assembly, the women's movement, including the National Assembly of Women, and the peace movement.

How can we make a more effective contribution to the fight against racism?

What more can be done in solidarity with the unemployed and people with disabilities in their battles against a cruel government, its benefit tests and its bedroom tax?

There is much to discuss and much to do.

In the interests of the working class and the people of Britain, in the interests of the labour, women's and peace movement, in the interests of the international communist movement, we must build the Communist Party of Britain.

And as we do so, let us bear in mind those words of Marx and Engels in the Manifesto of the Communist Party in 1848: "The communists fight for the attainment of the immediate aims, for the enforcement of the momentary interests of the working class; but in the movement of the present, they also represent and take care of the future of that movement."

The future of our movement, of Britain and of our planet is socialism.

Robert Griffiths is general secretary of the Communist Party of Britain. This article is an edited extract of his speech delivered to the 53rd Communist Congress at the weekend.