This article in the guardian by Prof Danny Dorling says that becasue we having an aging population and low birth rate, we need immigrants to support increasing high *dependency ratio. Many places in the developed world have a similar problem, and each will have to make themselves welcomimg enough to attract immigrants. If we lack the right attitude and enough well paid jobs, then we will loose out. Read here to see what Danny Dorling has to say
*dependency ratio -The number of children (aged under 15) and old people (aged 65
and over) related to the number of adults of working age(between 15 and 64). In other words, the first 2 groups are dependent on the last for support – too many dependents, and we have a problem!