Hundreds of the UK's top business leaders gathered for their annual conference in London on Monday and the timing could not have been more critical.

The country is still in the middle of its ongoing Brexit saga and it is less than a month from a UK general election.

So this meeting of the Confederation of Business and Industry (CBI) was always going to be an election sales pitch.

This industry body represents 190,000 UK businesses.

CBI director-general Dame Carolyn Fairbairn said investment in the UK was sluggish.

Investment in UK businesses has fallen in five out of the last 6 quarters. Fairbairn said the "world is watching" the UK and other countries feel "sorry" for it.

It was hardly a spirit-raising description of an economy that industry wants to sell to the world and declare is open for business.

The CBI never wanted Brexit, but since they are stuck with it, their focus has been on getting the best deal for business.

But it is not clear which party industry leaders will vote for in the election.

Most of all they want Brexit to be completed, with no dreaded "crash" out of the EU.

UK Prime Minister and Leader of the Conservative Party, Boris Johnson, had no apologies for trying to sell his election message to business.

In essence it was the usual "vote for me I'll get Brexit done and restore business confidence."

Johnson also promised almost $1.3 billion worth of business tax cuts, but cancelled a planned reduction in corporate tax rates.

His Labour rival Jeremy Corbyn bet his election program on a so-called Green Industrial Revolution. Labour wants to create 80,000 apprenticeships every year in the area of climate change. So 320,000 jobs in total.

It has also announced plans to part-nationalize BT to provide free high speed broadband internet to homes across the UK.

The CBI's Fairbairn said talk of nationalization caused "shivers" in boardrooms across the UK and abroad.

As for the Liberal Democrats, its leader Jo Swinson again promised to cancel Brexit if they win the election.

One of the other major concerns for the business community is immigration. After the UK leaves the European Union, EU citizens lose the automatic right to live and work in the UK without a visa.

The Conservative Party says if it wins the election it will introduce tougher immigration rules. But the UK depends on foreign workers especially in areas like construction.

Fairbairn says the country needs abbatoir workers, plumbers, bricklayers, painters and builders. And many of them now come from central and eastern Europe.

The Confederation of Business and Industry warns that a strict immigration system based on an Australian-style points system could lead to a shortage of skilled laborers.

And then there is Brexit.

If the UK does leave the European Union in January it still has to negotiate complicated new trade deals with the EU by the end of next year.

It is another tight deadline. So business confidence could remain shaky for some time to come.

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