New confusion surrounds party’s core policy issue on the day of its manifesto launch as cap – scrapped just weeks ago by Nigel Farage – returns

Ukip’s general election manifesto will reinstate a 50,000-a-year cap on immigration – a target that leader Nigel Farage scrapped just weeks ago – throwing new confusion over the party’s core policy issue on the day of its launch.

Suzanne Evans, the party policy chief, confirmed the U-turn as she set out how the manifesto would be a much more serious document than the 2010 one, which was later dismissed by Farage as nonsense and drivel.

She claimed its manifesto would be serious, fully costed and independently audited when it is launched later on Wednesday morning in Essex.

Speaking on BBC Radio 4’s Today programme, she said it would prove Ukip was “the party with the money” as it was prepared to raise around £30bn from leaving the EU, scrapping HS2, slashing foreign aid and giving less money to Scotland.

However, the party’s position on immigration appears to have changed again. Launching their immigration policies several weeks ago, Farage dropped plans for a target of 50,000 immigrants a year, saying targets and caps were not necessary. He then talked of a range of 20,000 to 50,000, a preferred number of 30,000 and a target of 20,000.

Now the 50,000 cap is back, with Evans confirming: “It talks about a target, a limit of 50,000 for skilled workers coming across from around the world. And this is the one thing about our immigration policy that I’m particularly proud of and that we really need to shout from the rooftops, I think: it is the only immigration policy that is fair, equitable and doesn’t discriminate.”

Ahead of the launch, Ukip’s immigration spokesman, Steven Woolfe, acknowledged there had been some tension over the issue.

He told Sky News: “I, like most people when you work with professionals who are working under intense pressure, sometimes have disagreements and I had a disagreement with Suzanne over a couple of points at that time, but they’re all cleared out.

“And when you see the manifesto today, you’ll see that we’re absolutely online with everybody able to understand how immigration works in this country.

“And it wasn’t just the fact that we saw with the media as well not understanding – when I was talking about 50,000 migration, it only related to highly-skilled workers, but a lot in the press were saying that was net migration as a whole and it’s much more complicated than that.”

Ukip’s other policies on immigration also include an Australian style points system for skilled workers and a five-year ban on unskilled workers, but Evans acknowledged seasonal workers might be allowed to come over on temporary visas or students could take their place working on farms.

Another pledge will be to bring back the “primary purpose rule” scrapped by Labour that forced immigrants to prove their marriages to British citizens were genuine. This was unpopular with many people because it meant foreign spouses and dependants of British citizens were prevented from entering the country.

At the time, the then home secretary Jack Straw said it was being ended because “it is arbitrary, unfair and ineffective and has penalised genuine cases, divided families and unnecessarily increased the administrative burden on the immigration system”.

Ukip’s 2015 manifesto is expected to be more realistic in tone than the 2010 document, which made a series of bizarre pledges such as making the Circle Line circular again and enforcing a dress code for taxi drivers.

It is understood the document, written by Evans and signed off by Farage, will pledge to increase defence spending, abolish hospital parking charges, give £12bn to the NHS, give £5bn to social care, fund an extra 6,000 police, border staff and prison officer jobs for veterans, and cut business rates.

The party also appears to have watered down its proposal to scrap stamp duty for homes built on brownfield sites, saying this would only apply to those worth less than £250,000.

Speaking in Essex, Farage will present his party as the only option that provides real change “for the first time in 100 years”.

A flavour of what the party will promise appears to have been released ahead of the launch by the Ukip Northern Ireland branch, which tweeted a copy.

During the campaign so far, Farage has struggled to break into the headlines, with the Conservatives and Labour presenting the election as a straight choice between Ed Miliband and David Cameron for prime minister.

Amid polls suggesting Ukip’s national share of the vote is falling, Farage told a rally on Monday night: “There is a very big squeeze being put on Ukip with the presentation of a binary choice ... But neither of the big parties are going to be able to form a government.”

The Conservatives rubbished Ukip’s claims to have a written a “fully-costed” document. A spokesman said: “Ukip saying their numbers add up is like Labour saying they’re not going to raise your taxes. We all know that Nigel Farage doesn’t have a credible plan for Britain.”

Ukip is only expected to win a handful of seats at the election but could influence the overall result through its share of the vote in marginal seats.