I have been on haemodialysis since july 2012. Currently I have developed numbness in both of my feet. What are the causes and possible solutions?

Depends. This depends as there are several causes of neuropathy (the paresthia or numbness you have). There are several metabolic causes that can cause neuropathy including diabetes, uremia, hypothyroidism, liver failure, amyloidosis, acromegaly, and nutritional/vitamin deficiencies just to name a few. With diabetes and uremia being most common. With your h/o kidney disease uremia is big possiblity.
Depends. Do u have diabetes? Could be neuropathy from diabetes. Regardless ask ur foot specialist. There are various drugs, physical therapy and injection therapy to help.
Numbness of feet. Numb feet may be caused by many conditions: diabetic neuropathy, alcohol or drug-induced neuropathy, radiculopathy from undiagnosed lower back problems, electrolyte inbalance (haemodialysis), etc. Please consult with your nephrologist and/or neurologist or podiatrist for a thorough examination.