Nick Clegg said the Vulcan was a 'good old fashioned' local pub
Liberal Democrat leader Nick Clegg took time out from his conference visit to visit a threatened Victorian pub.
The Vulcan Hotel in Adamsdown, Cardiff, is set to make way for a multi-storey car park, retail units and apartments.
Campaigners have called for heritage body Cadw to list the building and sent a 5,000-name petition to the assembly.
Mr Clegg said: "It's an important part of Cardiff's history, and with its tiled frontage and original features, it is an asset to the city centre."
He called in to pull a pint at the pub ahead of the party's Welsh conference, held at the Angel Hotel on the other side of the city centre, on Saturday and Sunday.
The Campaign for Real Ale or Camra estimates pubs in Wales are closing at the rate of five a week.
Last orders are set to be called at the Vulcan for the final time in June
Mr Clegg said Welsh Liberal Democrats were calling for the Vulcan, as one of Cardiff's oldest pubs, to be saved.
He said: "I have met many people all over the UK campaigning to save their local pubs. They are part of the lifeblood of local communities, and this good old fashioned local is no exception.
"It is very sad that this little Victorian pub is under threat."
Petition organiser Rachel Thomas, 25, said the campaign had received support across the political spectrum and was waiting to hear back from Cadw on the bid to have the Vulcan listed.
She said the pub had a mix of local people from Adamsdown and "creative students" from nearby university campus sites and halls of residence.
She said: "The series of meetings between the developer, the city council and the local MP and assembly member are on-going.
"I have a huge amount of hope. We submitted a petition to the assembly and 5,000 people is not a number that the assembly and the council can ignore.
"We're very hopeful that we're going to have the right outcome."
Last October, the National History Museum at St Fagans, near Cardiff, said it was keen to add a pub to its collection of buildings and would "gladly consider" preserving the 156-year-old Vulcan.
Last month, Conservative business spokesman Ken Clarke also visited the pub when he came to Cardiff.