When the beginning or terminal of a trunk highway is the state boundary, and the commissioner of transportation and the authorities of the adjoining state deem it desirable during the construction or improvement of such trunk highway to construct or improve a connector highway in the adjoining state thereby connecting or improving the connection of such trunk highway with the highway system of the adjoining state, the commissioner may enter into agreements with the authorities of such adjoining state providing for such connecting highway to be constructed or improved under and as part of the trunk highway construction contract. Such connector highway shall connect with the trunk highway at the state boundary. The entire cost of constructing or improving the connector highway, including engineering costs and expenses, planning and designing expenses, and any other expenses attributable to such connector highway, shall be paid by the adjoining state, and the manner and time of such payment shall be specified in the agreement.
The commissioner, in the interest of construction economy, may enter into agreements with the authorities of an adjoining state providing that the adjoining state construct or improve a segment of a Minnesota trunk highway route in conjunction with a construction project of the adjoining state so as to connect or improve the connection of the Minnesota trunk highway route with the highway system of such adjoining state at their common boundary. The cost of construction or improvement of such segment, including costs of planning and design and equitable engineering costs and expenses attributable to such segment, shall be paid from the trunk highway fund.