A record number of foreigners became British citizens last year, bringing the total since Labour came to power to almost 1.2 million, according to figures published yesterday.

Three quarters of those getting a British passport came from Asia and Africa with the main nationalities being Indian, Philippine, Afghan, South African and Pakistani.

The figure is 7 per cent up on the previous year and was the highest number ever granted in any year.

A series of reports released in Whitehall showed that 164,635 foreigners became British citizens last year, which followed a slump in numbers in 2006. The increase in the number of immigrants obtaining citizenship comes despite a drive by the Government to make it more difficult for people to become British.

In 2005 a Britishness test was introduced that makes foreigners take a multiple-choice test before being granted citizenship.

The Home Office said that reasons for the increase in 2007 were not clear but suggested that speedier decision making had reduced the backlog of applicants. More than 2,300 applicants were refused a passport because they had insufficient knowledge of English or failed the test on life in Britain.

Damien Green, the Tory immigration spokesman, said: “These figures are extraordinary. Given the Government’s proven record at granting passports to people like Muktar Ibrahim Said — ringleader of the July 21 plot — the public will be alarmed that passports are being handed out at such a rate. Given the Government’s ineptitude, how can they guarantee they are being granted to suitable people? This shows why it is essential our border controls are tightened.”

Nationalities with the largest number of citizens were Indian with 14,490, Philippine 10,840, South African 8,150, Afghan 10,555 and Pakistani 8,140.

While record numbers of people took citizenship, separate figures showed that the number of people who left the country in 2006 hit a record of 400,000.

More than half were British citizens, of whom almost one third went to live in Australia and New Zealand, a quarter to Spain or France and about one in twelve to the US.

An estimated 591,000 people came to Britain, resulting in net immigration in 2006 running at 191,000.

Net immigration of New Commonwealth citizens was 115,000 and was the highest of all foreign citizenship groups coming to the country. Citizens from India, Pakistan, Bangladesh and Sri Lanka made up 80 per cent of net migrants.

By comparison net immigration from the Old Commonwealth — Australia, Canada, New Zealand, South Africa — fell to 20,000 and from other countries dropped to 81,000.

London was the most common destination for immigrants with almost 30 per cent saying that the capital was where they intended to stay.

The Office for National Statistics (ONS) admitted: “However, immigration has become increasingly dispersed across the UK compared with previous years.”

Two other sets of figures produced by the ONS highlighted the changes caused by the scale of immigration since Labour came to power.

Figures for people coming to the country for less than a year have been dramatically revised upwards by 23 per cent for 2003-04 and by 22 per cent in 2004-05. An estimated 1.1 million short-term migrants came to Britain in 2004 and 1.2 million in 2005. This means that estimated immigration including both short and long-term migration was almost 1.5 million in 2004 and 1,750,00 in 2005.

The ONS also produced figures showing that 12.5 per cent of total employment is made up of non-British-born workers. The figures showed that in the first three months of 1997 the workforce comprised 24.3 million UK-born people and 1.9 million non-UK-born compared with the same period this year of 25.8 million and 3.7 million respectively.

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