Rejecting sponsorship and 'keeping the door open'.

Our funds for donations to organizations and advertising sponsorships have exhausted. Therefore, we regretfully inform you that we will not be participating at this time. Best of luck and thank you for considering us.

thank you for your help with the above. I would like to add a clause stating that maybe in the future when funds becomed available we would be able to participate...how shall i state that and where would I insert it