Pak population may touch 292m mark by 2050: seminar told - PakTribune
While the population of much of the world will start to decline soon because of low TFR, there are exceptions. One of them is Pakistan, which will continue to (naturally) grow. The USA will grow as well, but from immigration. Same for some countries in Europe. The UK is one of those countries. Its population will continue to grow in the long run, not because women there have children (TFR of 1.9), but because of immigration.
Guess where a great deal of that immigration comes from...Yep. Pakistan. So while British women are having children at below-replacement levels, the fertile women of Pakistan will continue to procreate quite well, thank you. And rest assured, the UK will continue to welcome them in.
And that is how London will become Londonistan indeed.