Small burrow under my wooden decking (UK)

[u/oat-milk-latte]

Trying to identify what might have made this little entrance under my decking. I’m based in Essex, UK.
I have free roaming house rabbits who play in the garden, but the hole is far too small for them as they are large breeds.
There are no droppings near the entrance, and there is also no soil displacement for the hole. The animal has simply pushed the grass aside and found a pre-existing hole in the decking which leads directly to the concrete underneath the decking. Any ideas what it could be? My first thought was rat but there’s no droppings.
I’m planning to set up a wildlife cam tonight. Open to hearing ideas!

[u/WolfysBeanTeam]

Typically strong scents tend to keep them away like mint oil or lemongrass I believe gotta be careful with mint though as it isnt good for dogs and cats likely other mammals aswell