Hi,
Firstly make sure that your pup has access to get outside by himself, can you leave a door open, as he will not ask to go to the toilet at this age, pups pee constanstantly at this age.
You are doing the right thing in staying with him, and I am dumbfounded that he will not go, especially upto 5 hours outside.

Firstly as soon as he wakes up in the morning, put him straight outside and stay with him, (I can't believe he won't wee then) praise him to the hilt when he does.
As soon as he has had a meal, or another nap take him straight outside,
Do not close the house door, leave it open and stay outside with him.
When he is inside the house watch him like a hawk the moment he begins to sniff the floor, or circle grab him and put him outside, show him a spot where to go, stand there and stay with him until he goes. Take him to the same spot each time you take him outside.
If you have not done so, clean all the pee areas in your home with bio, soap powders, ( not exactly sure what products are best, other kind members will tell you) continue to watch him and if you do everything above and it is still not enticing him to pee outside then wait until he starts to wee, grab him mid way ruuuun and pop him outside on the chosen spot to force him to finish out there, then praise him to the hilt.
The pup is only a tiny baby, so don't expect him to be 100% clean, some breeds take an awfully long time to toilet train, other pups are very quick to learn, praise and reward will teach him so much quicker.
It will all come together eventually, he is so young at the moment. :-)