Delete an External User (Before they access the invite link)

I have resolved this issue myself, so thought I would share  (in case other users have the same issue). 

To remove a user's access whilst their invite is "Pending", navigate to the "Access Requests" page as follows;

1) Open the SharePoint site this relates to

2) Click on Settings (cog in top right hand corner)

3) Click on "Site Settings"

4) Click on "Access Requests and Invitations" (under "Users and Permissions)

This provides a list of all External User Invitations that are still pending, click on  "..." next to the user name and a popup box appears with the option to "Withdraw".  

Now I write this, I cant believe it took me so long to find this. 

An alternative, (I stumbled across this accidently and worked my way back), is to use the following link;

https://<insert_sharepoint_name>.sharepoint.com/sites/<Insert_sub-site_name>/Access%20Requests/pendingreq.aspx?mbypass=1

Thanks