BBCA former Tyneside department store is to house an Indian government consulate.
JT Parrish traded on Shields Road in Byker from 1921 until its closure in the mid-1980s.
In recent years it has housed students, although its ground floor is currently unoccupied.
Much of the building is earmarked for a new Ibis hotel, but one floor will now house the only Indian consulate between Edinburgh and Birmingham.
The opening was marked by the unveiling of a plaque by Vikram Doraiswami, High Commissioner of India to the United Kingdom.
He said the consulate would deal with any issues arising for Indian citizens in the country, whether temporarily or permanently resident here.
It would also offer help for companies in the region which want to do business in India.
“The kind of services we offer [at the embassy] in London include business matchmaking, connecting you to potential partners, buyers or sellers in India,” he said.
“We’d like Newcastle to become one of the spokes in our larger hub.”
The JT Parrish department store building is owned by the Tyneside-based Malhotra Group which has built up a large property portfolio across the region, as well as having an interest in care homes.
It also has commercial property developments in India, the home country of its chairman, Meenu Malhotra, who is now a British citizen.
“I wear two hats,” he said. “I am a proud Indian and I represent the region of the north east of England, which has accorded me fulfilment and pride for 45 years.”
Byker’s Shields Road is regularly traduced as being the “worst high street” in the UK, thanks in part to the number of empty units.