No person shall operate a public vehicle, nor shall any license be issued hereunder, until the applicant for such license deposits with the Director of Public Safety a policy or certificate of liability insurance for each public vehicle for which a license is sought, acceptable to and approved by the Director and Solicitor, indemnifying the applicant in the sum of at least one hundred thousand dollars ($100,000) for injury to one person, three hundred thousand dollars ($300,000) for injury to more than one person and ten thousand dollars ($10,000) property damage in any one accident, through the operation of the public vehicle by the applicant. The policy shall further contain a clause obligating the insurance company to give ten days' written notice to the Director before cancellation of the policy. Upon the lapse or termination of the policy of insurance, the licensee's license shall automatically expire.