This blog by Joe Anderson is succinct and well put. 

Spending remains 2.6 times higher in London than in the North, a huge difference. In pounds and pence in the single year of 2016-17, there was a £9bn difference in spend. 

These figures need to be seen in the context of the announcements for additional spend in the North to date, where we have seen figures for annual increased spend amounting to less than 3% of that £9bn difference. While the imbalance in spend (and therefore the development of infrastructure) continues, the gap between the North and South can only increase.

The benefits of connectivity to enable business to business engagement and to provide access to a wider consumer base and talent pool are clearly visible in London. They continue to be heavily invested in from the public purse. It is surely time to see similar sums being invested in real time and in real terms in the North.