I have a staff whose review came in a month ago ago & he advised me verbally that he will be resigning his job because the experience he is acquiring from his exisitng job is inadequate for him in advancing his career.

I have made it clear that as per the terms of the Contract he has to give me a month’s notice albeit the contract does not specify whether the notice has to be in writing or can be verbal.
I have asked the staff in question to put it in writing but he refuses to do so & advices me that he will only put it in writing when he secures a new job.
No one has been a witness in our meeting to date & he refuses to discuss this matter in front of any other unbiased third party.

I have adviced him that this is causing uncertainty in our planning as I cannot decide when to start looking for an alternative replacement. Furthermore, I can hardly trust this person any more.

I know that his chances of securing a new job are being hampered by 1 month’s notice on the Contract so he is playing it safe at present.

My question is can how do I overcome this problem so that I am not seen to be dismissing this person unfairly & can get on with recruiting a new staff?