The UK has little troops down there and loss of Africa to Germany will dwarf its income.
Landing in Algeria to reclaim it is a long way until the last corner is liberated.
Two National Advantages may help:
1. Enigma Decoded
G1 Angloegypt is attacked. Use it to save your fighter and tank.
The fighter to counterattack on your turn, the tank to do the same or to reinforce India.
You just saved 15 ipcs and more important two fast units to preserve your flexibility in this region.
2. Colonial Garrison
Placed in South Africa. 2 units to build each turn- that matches the german transport capacity. Start with inf art- the cheapest way to kill a blitzing tank.
This complex makes it very costy for both Germany (early game) and Japan (mid game) to contest the continent. They will need additional transport capacity for this task. And the more troops are dedicated to a long african campaign the smaller the forces marching to Moskwa.
Conserved wisely the Pacific Fleet will threaten the Mediterrean and the southern japanese attack prong via India an Persia. Combined with the australian sub/trans it will have a considerable defense strength. Buy cheap ground troops and a third transport and you will have six divisions as invasion forces. Enough to cause the Axis a serious headache considering all possible landing spots. But take care there might cruise some super heavy btls out there in the Pacific- make it through the channel before they arrive.
In combination these two NA will maintain UK control of the black Continent. It is effective much earlier than the Algeria approach, where even a combined UK/US landing has to turtle and advance slowly facing the majority of german airforce in reach.
The cost for 2 ground troops are between 6ipc for 2 inf to 10ipc for 2 tks. There should be sufficient cash left to bolster up the Homefleet or to train troops on the island.