Soaring property prices mean that first-time buyers are forced to “pay double” in London to get on the housing ladder, a new report reveals today.

The average buyer in the capital has to find £420,132 for a first home, almost twice the £210,515 typical for the rest of Britain, according to research from Lloyds Bank.

It found that the average price has soared by close to two thirds over the past five years despite the slowdown at the top end of the market, particularly in central London.

The average deposit paid by a first-time buyer in London is £92,833, more than 60 per cent higher than in 2013. The highest deposits were in Camden where they average £175,844, a 28 per cent jump from £137,079 five years ago.

Haringey has seen the biggest increase in deposits paid by first-time buyers. They have more than doubled from £63,447 in 2013 to £131,827. The size of the average London first-time-buyer mortgage has also soared — by 65 per cent in the past five years to £327,299, compared with £170,847 for the rest of the UK.

The figures suggest that “generation rent” still face a near-insurmountable challenge to get on the first rung of the ladder without a major financial leg-up from their families.

Levels of home ownership among the under-40s have plummeted over the past decade as buy-to-let, foreign investors and demand from London’s growing population have forced up prices.

Government schemes such as “Help to Buy” — aimed at young buyers — have also underpinned prices.

Just 16 per cent of 25 to 34-year-olds in outer London owned the roof over their heads last year compared with 53 per cent at the height of the Thatcherite revolution in the Eighties.

Five years ago 17 per cent of all first-time buyers in the UK were in London, but today that proportion has fallen to 12 per cent, according to the Lloyds data, suggesting that many millennials are giving up on the capital.

However, it is still cheaper to buy than rent, according to Lloyds. A typical three-bedroom house would cost a London first-time buyer about £1,248 per month with the rent for a similar property coming in at £1,545.

Andrew Mason, Lloyds Bank mortgage products director, said: “Despite the recent slowdown in London house prices this latest data shows how expensive it has become to live in the capital, particularly for young people trying to get on the ladder for the first time. As a result, first-time buyers have to wait until they are 34 before getting their first foot on the property ladder.”

“While property prices drop as you head to the fringes of the capital, our analysis is showing that this gap is closing as house price growth in outer London boroughs is continuing to increase at a greater pace than inner London boroughs.

“This healthy growth may be linked to a high demand for these more affordable properties as well as some areas benefiting from the new Crossrail link due to open next year as commuters move further afield.”