Britain is set to experience more terrorism, global warming and increased polarisation as rich and poor lead separate lives, according to a Government report.

The gloomy analysis appears in a study by the Strategy Unit, a Government body created to think about the long term challenges facing Britain.

Examining the findings was one of the first responsibilities of West Midlands MP Tom Watson (Lab West Bromwich East) as he began his new job as a Cabinet Office Minister, following Prime Minister Gordon Brown's reshuffle last month.

Mr Watson, whose role is to help to coordinate Government policy across departments, has invited readers of his website to read the report for themselves and give their thoughts.

But although it also contains plenty of good news, such as predictions that the economy will remain strong and crime will fall, the 184-page study is unflinching in its analysis of the challenges the nation faces.

It makes a number of predictions for the future, including

* The number of jobs for low-skilled workers will fall - and those that are left will pay less - as jobs are off-shored to China and India

* The married population will fall from just under 22 million in 2003 to 20 million by 2031, while the divorced population will increase from 3.7 million in 2003 to 5.1 million by 2031

* Poor and rich households will become less likely to live next door to one another. Neighbourhoods will tend to be either rich or poor, with fewer containing a mix of people

* gun crime appears to be falling, but children are also being drawn into gun and gang crime at a younger age

* The number of people involved in radical and violent extremism in the UK has grown in the past ten years. The report warns: "The scale of the threat is potentially still increasing and is not likely to diminish significantly for some years"

* There will be increased demands on public services because of "high levels of immigration". The report highlights rising pupil numbers in some schools, and the growing number of pupils who do not speak English fluently

* An increased risk of flooding and severe heat waves in the UK is "inevitable in the next 20-30 years"

* Global temperatures are expected to increase by at least 3C (37.4F) by 2100 if decisive action is not taken.

The report, called Realising Britain's Potential - Strategic Challenges for Britain, sets out changes the country needs to make in order to succeed in the 21st century.

It calls for a more favourable approach to enterprise, pointing out that entrepreneurial activity in the UK is still roughly half the rate of the US.

The report also calls for a focus on neighbourhood policing and measures to target potential criminals at an early age.

And it warns that Britain needs to develop low-carbon technology to beat climate change.

But it adds: "Attitudes and behaviours will have to change, both from business and from people generally.

"People will have to take action in their daily lives to prevent emissions, eg walking and cycling more."

Gordon Brown, writing in the report's introduction, focused on the need to improve skills and education.

He said: "We cannot, and would not want to, compete on low pay against countries where unskilled workers are paid a twentieth of their equivalent workers here in the United Kingdom.

"Instead, Britain's imperative - and our opportunity - is to lead in high value added services, high value added manufacturing and research, science and innovation.

"To achieve this we need to be world-class in innovation, world class in creativity and world class in education - making use of the skills of all our people and breaking down all the barriers that hold talent back. Over the coming months I intend to focus relentlessly on how we remove those barriers, raise our national aspirations and increase the opportunity for lifelong learning and re-learning, with the ambition of realising the potential of everyone in this country."