Hi, Thank you for your question and welcome. I do not think this is a matter for the police. Essentially it is not fraud or theft as he has owned up and intended to repay the debt. For it to be fraud or theft he has to have a dishonest intention to deliberately deprive you of the money. This sounds like someone who had agreed to pay it back but has become desperate from unemployment. You can report it to the police but it is likely to waste time and if he does not have the money you wont get it back and all he will end up with is a criminal record if convicted. I suspect the police will say it is a civil matter.
What I suggest you do is either:
1. https://www.moneyclaim.gov.uk/web/mcol/welcome - start a money claim against him.
If he has no money this may be good money after bad;
2. What until he gets another job - as you have 6 years to bring the claim;
3. Try and agree another repayment plan.
The danger is if you push him too hard he may just decide to go bankrupt and then you will get nothing. Really court action should be considered if he actually has some means to pay you back.
Kind regards AJ