New Delhi, Sep 25 : Air India will add its 'AI' designator code to over 100 flights a day operated by Air India Express on 21 routes while more routes under the codeshare agreement will be added progressively, an airline official said on Monday. According to airline spokespersons, bookings for the codeshare flights are being opened across points of sale, for travel starting on Monday. The codeshare implementation enables Air India guests to connect seamlessly on Air India Express' route network to and from over 80 points across Air India's extensive domestic and international network. The scope of the agreement between the two airlines enables passengers to receive their boarding passes at the first point of departure for all the travel sectors on a single ticket, and have their baggage checked-in through to their final destinations. "Guests connecting from international to domestic flights will, however, need to clear customs at the first point of entry in India, in line with government regulations," said the spokesperson. "With the implementation of the codeshare agreement, Air India has expanded its domestic route network to four new destinations in India, namely Bagdogra, Bhubaneswar, Ranchi, and Surat, in addition to the common destinations between the two airlines' route networks. Passengers from these originating cities will be able to connect to Air India's wide international network over hubs at Delhi and Mumbai," said the spokesperson. The codeshare agreement also enables AIX Connect to leverage Air India's global distribution network, via the airline's direct channels as well as its global travel agency network. /IANS