Boarded-up shops and crippling business rates would be targeted under Sir Keir Starmer's new bid to reverse the decline of town centres.
The Labour leader was speaking on a visit to Great Yarmouth alongside his shadow chancellor Rachel Reeves at the launch of a five-point plan to revitalise local high streets on Wednesday.
The pair strolled down Regent Road and passersby stopped for a quick photo and a chat.
Starting inside the Fish 'O' Licious restaurant, Sir Keir and Mrs Reeves had a private conversation with several local business owners before speaking out against "13 years of decline for beloved local shops, pubs and entertainment facilities".
Sir Keir said: "Empty shops and boarded-up shops destroy high streets.
"Because that's not just a failed business, it has an impact on other businesses and makes it much less likely that people will come into the high street. That leads to a downturn for everybody else."
There are currently seven empty commercial units in Great Yarmouth town centre.
Sir Keir said he wanted councils to work with landlords to see whether businesses could be revived. He said councils should have more power to intervene when shops remained empty.
He said: "If you walk down any high street and ask the businesses that are still here, 'would you like your council to do something about the boarded-up premises,' they will say, 'yes because it's impacting me and my business'.
"And we want a government that understands that and does something about it."
Mrs Reeves said business rate reform would help councils find new tenants for commercial spaces.
She said: "You need to give local authorities the flexibility to reduce business rates when businesses move into empty properties.
"Many high street businesses say to me - both here in Great Yarmouth and around the country - that business rates are one of those taxes that you have to pay before you make a penny of profit, even a penny of turnover.
"And at the moment, many businesses are really struggling to make any sort of profit and business rates can often be crippling.
"Which is why the first pledge in our five-point plan for the high street is about the reform of business rates."
Stopping off at Docwra's Rock Factory, Sir Keir and Mrs Reeves packaged sticks of rock and spoke with manager John Burnham.
Mr Burnham said: "They seemed very nice people. We talked about the local area and what the season's been like so far and what we're expecting.
"Reducing rates and filling up empty buildings on any high street or seasonal area which is reliant on a very short window of trade wouldn't hurt. Anything which could help with running costs would be great."
Labour's new plan also includes cutting energy bills, stamping out late payments, revamping empty shops and tackling antisocial behaviour.
Sir Keir and Mrs Reeves continued down Regent Road before buying coffee at Sweet Creams ice cream parlour.
As soon as the opposition leader entered the premises, a customer said: "Oh, it's Keir Starmer. Oh, hello."
They went on to have a chat about football.
Sir Keir also spoke about how his party would approach other issues Yarmouth residents face.
When asked about the housing of asylum seekers in seaside hotels - including two in Great Yarmouth at the end of last year - Sir Keir said: "I completely understand the local concerns about hotels and the cost that is implied with that.
"The root cause is the government has broken the asylum system.
"That has to be changed, we have to tackle the criminal gangs that are running these dangerous crossings and we have to stop the boats."
Keir Starmer's thoughts on coastal erosion at Hemsby
During Sir Keir Starmer's visit to Great Yarmouth on Wednesday, the Labour leader said the eroding cliffs at Hemsby - and other coastal towns in the country - have a huge impact on communities.
Recently, the village has seen a temporary rock berm installed following high spring tides, which claimed two roads on The Marrams and led to five homes being demolished.
Sir Keir said: "Firstly, I would like to express my empathy with those affected by this. Because a number of houses have been lost, it has a huge impact on communities.
"And I completely understand how concerned they will be.
"I think there is a package now to try to address this and we need to work with communities, to work with local councils to put forward a sustainable package to deal with this. But I completely understand why it is such a cause for concern."
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