The city of Shenzhen in southern China's Guangdong Province knotted friendship city ties with Edinburgh Tuesday.

The mayors of the two cities signed the agreement in Shenzhen at the 2019 Shenzhen Smart City Forum with International Friendship Cities, planning to cooperate on smart city building.

Shenzhen will hold discussions with its friendship cities to take advantage of the breakthroughs in science and technology and industry reform and find a way for cities' future development, said Wang Weizhong, the city's Party secretary.

Shenzhen has so far knotted friendship city ties with 87 provinces, districts and cities in 56 countries since it first started to knot friendship city ties in 1986.