It is agreed and understood that otherwise subject to the terms, exclusions, provisions and con itions contained in the Policy or endorsed thereon and subject to the Insured ha ing paid the agreed extra premium, the third party liability cover of the Policy hall apply to the insured parties named in the Schedule as if a separate policy ha been issued to each party, provided that the Insurers shall not indemnify the Isured under this Endorsement in respect of liability for