There has been a significant development today in the attempt by eurosceptics to coalesce under a single campaigning group - with the disclosures that Ukip, the ideologically eurosceptic party led by Nigel Farage, has thrown its official weight behind Grassroots Out.

This could potentially turn Grassroots Out - set up by two Tory MPs, Peter Bone and Tom Pursglove, and the Labour MP Kate Hoey - into the main eurosceptic organisation for the forthcoming referendum on whether we should remain in or quit the EU.

To date, the campaigns to leave the EU have been characterised by two trends: rising public support for quitting Europe and internecine strife (vicious civil war, to you and me) between what were hitherto seen as the two main campaigning groups, Leave.EU and Vote Leave.

So it matters that today Ukip, the ideologically eurosceptic party led by Nigel Farage, has thrown its official weight behind yet another campaigning group, Grassroots Out.

In another significant development, Leave.EU has also told me that it will slot in under Grassroots Out, and will give up any ambition to be the designated campaign.

Mr Farage told me that Ukip has formally decided to associate itself with Grassroots Out, because Leave.EU and Vote Leave had both been damaged by their constant fighting.

Grassroots Out has set up a top board, on which will sit three supposedly non-political business people. It will now try to trump both Leave.EU and Vote Leave by applying to the Electoral Commission to become the designated "leave" campaign.

Britons will soon decide whether the UK should remain inside the EU. Credit: PA Wire

I know this sounds desperately dry and technical. But it matters, because if Grassroots Out succeeds in getting the blessing of the Electoral Commission, it will have huge financial resources, access to TV advertising, a mail shot, and for broadcasters like ITV it will be the official spokesman for the leave campaign.

Under the rules, the designated campaign can spend up to £7m. UKIP as a political party can spend a further £4.4m, And all other the campaign groups sitting underneath - and Mr Farage told me there may be up to 40 of those in Britain - will be able to spend £700,000 each.

He told me he felt Arron Banks, the wealthy businessmen who created and funded Leave.EU, would direct a growing share of his resources to Grassroots Out.

So this umbrella approach would give the remain in EU campaign, Britain Stronger in Europe - which has raised millions of pounds - a run for its money.