Don’t know about GB, but the US has laws against corporations engaging in this kind of stuff.
Yes, but they are circumvented all the time. Many years ago, I worked for a publicly-held company that sold equipment to the Spanish telephone company. We had to pay 12% “commission” to certain offficials on every shipment. Any sales to Iran required a 15% payment to the Shah of Iran. Some countries were as low as 10%. This is common in almost every country in the world. The problem with shipping stuff to Africa is that there are many levels of payoffs needed.