Lessor shall comply with all Federal, state and local laws applicable to the Lessor as owner or lessor, or both, of the building or premises, including, without limitation, laws applicable to the construction, ownership, alteration or operation of both or either thereof, and will obtain all necessary permits, licenses and similar items at Lessor's expense. The Government will comply with all Federal, state and local laws applicable to and enforceable against it as a tenant under this lease; provided that nothing in this lease shall be construed as a waiver of any sovereign immunity of the Government. This lease shall be governed by Federal law.