Lessee shall be responsible for paying, and Lessor shall be responsible for collecting from Lessee and paying over to the appropriate authorities, all applicable Federal transportation taxes and sales, use or other excise taxes imposed by any governmental authority in connection with any use of the Aircraft by Lessee hereunder. Each party shall indemnify the other party against any and all claims, liabilities, costs and expenses (including attorney's fees as and when incurred) arising out of its breach of this undertaking.