Shand said he was taking legal advice on an injunction and was planning a community meeting to take place next month.
Whanganui District Council planning manager Hamish Lampp said the tower was given the green light in April and resource consent was not required under the District Plan.
"Whanganui District Council issued a compliance certificate to Spark New Zealand on 15 April 2019 for the construction of a telecommunications tower at 59 Jones St, Whanganui East," Lampp said.
"Compliance certificates do not require public notification."
Bikramjeet Singh, of Merchants Liquor Wanganui, which operates in the shopping centre, said he was not concerned by the tower.
"We are all dependent on internet and the internet is very slow over here," he said.
"Technology advancement is good and hopefully people in Whanganui East can get better network services as well."
Singh said the landowner had informed shopowners about the project before work began, and contractors had also communicated with shopowners about the work site.
Staff in other nearby shops also didn't have an issue with the tower.
In a statement, Spark said the site would deliver much-needed 3G and 4G services and was being built with the permission of a private landowner under a lease agreement.
"The Whanganui area has seen unprecedented growth for digital services with community data usage increasing by over 1500 per cent in the last three years.
"Mobile and data connectivity is currently being delivered to Whanganui by an existing site that is reaching full capacity. This means that as more users demand services, soon the existing site won't cope and users will start to experience issues like dropped calls, loss of connectivity to services and coverage issues.
"This loss of service has the potential to affect day-to-day accessibility to services, business efficiency and connectivity issues during emergency situations.
"Telecommunication facilities need to be placed where people and businesses can benefit from them the most and that means sites need to be in areas where people live and work."
Spark notified residents adjacent of the planned site following guidelines outlined in the NZ Telecommunications Forum.