Shadow chancellor Anneliese Dodds says that coronavirus testing would be her first priority, saying it is the best way to rescue the economy, save jobs and protect businesses.
The Labour MP welcomed much of what was announced by Rishi Sunak in his Coronavirus Jobs Support Scheme on Thursday, but questioned why there wasn't more focus on fixing testing, amid concerns about a lack of availability.
She told the ITV News podcast Acting Prime Minister that if she was in Mr Sunak's position, the "very first thing" she'd do would be to "work very hard indeed on why the test, trace and isolate system in the UK is not working as it should do".
"The fact that we are unfortunately behind lots of other countries on those public health measures clearly has led to additional restrictions being imposed, it's reducing people's confidence, about everything from going into a business to investing if they run a business."
"The chancellor said this week that £12 billion had been spent on that system but it's not working as it needs to so that would be the absolute first thing that I would do because it underlines everything else."
She also said the chancellor should have focused more on retraining workers and rebuilding businesses in order to avoid "1980s style levels of unemployment".
Also in the podcast, Ms Dodds told presenter Paul Brand what she thinks the biggest differences are between current leader Sir Keir Starmer and Jeremy Corbyn.
Ms Dodds is one of the few members of the current Shadow Cabinet who had a senior role under Mr Corbyn's leadership - she was in John McDonnell's shadow Treasury team before replacing him to become shadow chancellor when Mr Starmer took over.
She said the main difference between both leaderships is the level of "honesty and openness" under Mr Starmer.
"We really needed to move forward as a party and understand why people were rightly very unhappy with what had been happening previously, we needed to do something about those matters and do so speedily.
"That is new leadership, it's that new decisive leadership, dealing with those problems, being on people's side and being open to what they're saying to us."
She added: "Above all, there is that honesty and openness to understand where we may have gone wrong before."
The Labour frontbencher also admitted that she had already called the authorities on a business she thought was in breach of coronavirus rules, but said she said the "personal tough is best".
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When asked if she would call the police on her neighbours over coronavirus violations, Ms Dodds said: "When I've been in situations previously where I think something isn't right then I kind of have a quiet word with the person.
"I was in a situation at one point where I thought a business probably wasn't following the rules, I wasn't totally sure, but I contacted local environmental health so they could go and have a discussion with that business, then that got sorted out so they were totally clear about what the rules were.
"Often informally we can deal with these kind of issues before it has to get to a stage of formal enforcement but obviously if the latter is required then it's required and we need to make sure that we are all sticking to those restrictions."
She also opened up about her personal life in the podcast, revealing what it's like to be the shadow chancellor, scrutinising the government during a pandemic, while also being a mother to two young children.
To hear a more personal side to Ms Dodds, check out the whole podcast, which is available in video at the top of this page, or in audio below.