Discussions in mediation are held without prejudice or on a legally privileged basis. This means that what is said in mediation is confidential, save for some limited exceptions (which include sharing the information and discussions with your solicitor so that you can obtain legal advice). The contents of those conversations must not be disclosed to a court.
Disclosure provided in mediation is not however privileged. This means that although negotiations and general discussions remain private, any information you provide relating to your financial circumstances may be relied on by the other party in open correspondence, or even litigation. It is therefore essential, as noted above, that you enter the process with open hands, willing to provide full and frank disclosure as to your financial circumstances.