Greggs was forced to announce the closure of its 2,050 UK branches on 23 March, when a lockdown was put into place by the government, but plans were in place to reopen branches.
In late March, the high street bakery chain announced it was planning a phased re-opening of 20 branches in Newcastle (the original birthplace of the bakery), with sites due to open from 4 May for takeaway and delivery as part of an initial trial, which was set to last at least two weeks.
However, now the Greggs stores will run the reopen trial "behind closed doors" due to fears customers will flock to its stores in large numbers.
A company spokeswoman said: "Due to significant interest in our 20-shop trial, and the risk that excessive numbers of customers may plan to visit Greggs, we will now initially operate these trials behind closed doors in order to effectively test our new operational safety measures.
"We will continue to review this and will invite walk-in customers into our shops only when we can be confident of doing so in the controlled manner we intended."
The reversal of the plan, which was first reported by the Financial Times, comes after rivals such as Pret A Manger have reopened a small number of sites for takeaway and delivery.
Other chains reopening for delivery include Burger King and KFC.
Greggs had intended to open the 20 sites to see if it could operate effectively within the current social distancing guidelines.
Chief executive Roger Whitehouse previously said he hoped to open around 700 stores, including 150 franchise shops, with new operational measures in place from June 8.
It intended to then open all of its 2,050 stores by 1 July, when the Government's current furlough support package is due to end.
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