Partial Settlement - Unsure

[weebella]

I have been pursuing the Clydesdale Bank for charges of £3,073.50.
2 weeks ago they wrote to me offering £1,982.50 as a full and final settlement (they still stated they were not at fault, was my fault).
I wrote back stating I would accept their offer as a part settlement but if I did not receive the remaining sum would pursue in a court action.
They wrote back last week stating they were sorry I did not accept their offer and if I cashed their cheque they would accept this as the matter closed. Did not offer to repay the remaining amount.
Not sure how I stand legally. If I cash the cheque, can I still go ahead and raise a claim for the remaining amount or should I return the cheque and pursue the full amount in a court action?
I don't want to accept this part offer. I feel I would be giving in and letting them get their own way.
Their time is up today and I have not received the outstanding amount. Do I start a claim for the full amount or amount less the cheque. I will have to start process my claim tomorrow. I appreciate any advice.

[buzby]

No. They've made it clear the cheque is in 'full and final' and encashment will be acceptance of this. Return the cheque with a note stating that as the bank is unwilling to allow it to be used as part payment, you are returning the cheque and your court papers will be servied shortly.