Unclean Tenant refusing to pay rent due to condition of kitchen.

Possession - Section 8 and Section 21

What's the quickest way to evict a tenant? Refused to pay rent unless I pay for Pest control to deal with mice issues in kitchen, kitchen cleanliness is in a poor state, food waste on floor, on worktop, oven Co ered in greese, gas hob covered with food, workspace and backslash splattered with grease and bits of food. Never kept clean, whole kitchen and flooring replaced in 2019 due to uncleanness and also previous visit from pest control whom informed me the kitchen is very unclean. Tenant not taking action to clean, refusing to pay rent unless I clean up behind him and his family. To date 1 month rent unpaid, rent was due 06.09.2021