Determined Walnut Tree supporters are continuing with their campaign despite Tesco's submission of planning applications for the site.
More than 2,000 people - including Warwick and Leamington MP James Plaskitt - have signed a petition to oppose the supermarket's plans to convert the Cubbington Road pub into an 'Express' store.
The pub's supporter's this week launched an e-petition on the 10 Downing Street website and has a Facebook group with 122 members.
But on April 1 Tesco put forward four separate applications to Warwick District Council for making changes to the building.
District councillor Alan Boad (Lib Dem, Leamington Crown), who has been attending meetings held by the pub's campaigners, explained that because of government guidelines, converting pubs into shops does not require planning permission.
He said: "As we suspected, Tesco has been very clever.
"The pub can close tomorrow, Tesco could open there the next day and there is nothing we could do about it because the rules are clear."
Coun Boad said Punch Taverns, which owns the Walnut Tree, had told the pub's supporters it would look into other possibilities for the pub.
He added: "I am disappointed - it looks like they just want the money.
"If a Tesco store is put there, it will be a big problem - there will be an increase in traffic at an area that will not be able to take it.
"We are fighting it and we will be opposing it on whatever grounds we can find."
Campaigner and Lillington resident Gary Timlin added: "The fight intensifies. We're just playing it by ear but we are determined."
The proposals put forward included putting up shop signs, making changes to the outside of the building, installing air conditioning and refridgeration equipment, building an extension to the back of the building and converting the first floor to a flat.
Tesco has said the store will bring more jobs and businesses to the area.
A spokeswoman said this week: "The pub already has signage and refridgeration, so the applications are simply to change what is already existing."
Campaigners held a meeting at the Walnut Tree on Tuesday evening.
Speaking on behalf of the group, Jane Padginton said: "We believe the recent planning applications submitted by Tesco simply prove that the campaign to save the pub and local shops is a worthy and just cause.
"The plans prove that little consideration has been made as to the impact of lorry deliveries and the impact it will have on an already busy junction.
"With the limited access they would have to make deliveries and the proposed lengthy opening hours, we again feel this proves there would be a large impact on residents with lorries dropping off at anti-social hours of the day - or limited access to parking if made during the shop's trading hours."
She added: "The group continues with strengthened resolve. Our petition now has 2,400 signatures - and the list is still growing.
"The fight to save the pub may in time be lost - but we certainly haven't lost the war to stop Tesco blighting our community."
Anyone wishing to add their name to the petition should visit petitions.number10.gov.uk/walnuttreepub or www.savethewalnuttreepub.com
Punch Taverns, which also owns the Sarah Siddons pub in Warwick, this week announced plans to keep the Warwick premises as a pub, following overwhelming opposition to Tesco's plans to convert the site into an 'Express' store.
Warwick and Leamington MP James Plaskitt told the Courier he has written to Punch Tavern's chief executive to ask him to review the company's position on the Walnut Tree.