Nigel Farage and Chris Grayling
Ukip leader Nigel Farage and House of Commons leader Chris Grayling at a Grassroots Out rally on 18 AprilGetty

Nigel Farage has attacked fellow Brexit campaigners for failing to focus on the issue of immigration in the run-up to the EU referendum. The Ukip leader urged the official 'leave' campaign to make a bigger deal of the subject and claimed Eurosceptic cabinet ministers, such as Justice Secretary Michael Gove and House of Commons leader Chris Grayling, lacked credibility on the issue because of the government's failure to reduce net migration to the "tens of thousands".

"What we need to do, what the leave campaign needs to do and what I urge Vote Leave, the official designated vehicle, we have got to get into the other half of the pitch – we have got to start attacking the enemy's goal," Farage told a Westminster audience on 29 April.

"And where the enemy are at their absolute weakest is on this whole question of open-door migration, the effect that it has had on the lives of ordinary Britons over the course of the last decade and the threat that it poses given the new terror and security threat that we face in the West."

This is what you really need to know about the Brexit voteIBTimes UK

The Eurosceptic firebrand also claimed the "Westminster set" welcomed net migration levels running at more than 300,000 a year. "I guess it's because so many of them come from privileged and wealthy backgrounds and so rarely ever dare stray outside the M25," he declared.

"That they think open-door mass immigration is terrific and in some ways for them it is. Because it's cheaper nannies, it's cheaper chauffeurs and it's cheaper gardeners.

"But the impact of those has been felt by ordinary, decent people in this country. Just think about housing, here we are in London with a massive, massive housing crisis and we know the Green Belt is under threat. Is it any wonder? Given the current levels of immigration in Britain we have to build a new house every seven minutes just to cope with the current flow of people."

Ipsos MORI survey
Concerns index Ipsos MORI

Ipsos MORI's concerns index continually ranks immigration as a top issue for British voters, with the pollster's latest survey putting it ahead of the NHS/health, the EU and the economy.

Farage may have claimed Vote Leave is failing to sufficiently campaign on the issue, but Labour MP Frank Field and Gove have raised the issue at the group's recent media events.

Farage insisted his party will campaign heavily on the subject and try to push it to the top of the EU referendum agenda.The Ukip leader boasted that he had the activists to campaign independently of Vote Leave. IBTimes UK asked Farage if he had a war chest to match his enthusiasm.

"Am I going to be able to raise and spend £4m ($5.8m) quid in that six-week period? Yes. Do I have it all at the moment? No. Am I going to get it? You bet you I am," he replied. The £4m figure relates to the spending limit the Electoral Commission have given Ukip. However, Vote Leave is able to spend £7m and will be awarded a grant of up to £600,000 after winning the 'leave' designation from the watchdog.