Boris Johnson’s admiration for Donald Trump will lead to workers’ rights being ripped up if the Conservatives win the general election next month, the leader of Britain’s trade unionists has warned.

Frances O’Grady, the general secretary of the TUC, said a lack of detail in the Tory party’s manifesto disguised a hidden agenda of US-style deregulation of the sort favoured by the US president.

In an interview with the Guardian, O’Grady said: “We are very concerned that Boris Johnson will use Brexit as an opportunity and a licence to rip up workers’ rights.

“But it is worse than that. His infatuation with Donald Trump could drag us to an economic model that is really bad for working people. Trump has got his fingerprints all over the Tories.”

O’Grady said the election provided a choice between two competing philosophies, adding that fundamental rights were at risk.

“The question is what is going to happen in Britain under Boris Johnson – not just a hard Brexit but a turn towards the US and a Trump way of organising working life.”

O’Grady said that in the US it was far more common for workers to be on zero-hours contracts, there was no national protection against the sack, no statutory sick pay, no holiday pay and no maternity pay.

Facebook Twitter Pinterest Frances O’Grady says Donald Trump has ‘his fingerprints’ all over the Tories. Photograph: Will Oliver/EPA

“Is that the model we want to follow? We know that Boris Johnson is a big admirer of Donald Trump.” In a reference to the president’s love of golf, she said: “We talk about becoming Trump’s poodles, but you could say there is a risk of becoming Trump’s caddies.”

The Conservatives have announced the biggest increase in public spending in 15 years and pledged to increase the “national living wage” to £10.50 within five years as part of a strategy designed to appeal to blue-collar voters in Labour’s traditional heartlands.

O’Grady said she did not believe in the rebranding of the Conservatives as the party of working people.

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“The Conservatives have form. It is not the first time they have tried to appeal to blue-collar voters nor the first time that they have underestimated them. Working-class voters know that families matter and they know what the parties are offering families.

“The manifesto is so thin the question must be what lies behind it. Do we trust them? No. Do we think there is worse to come? Yes. Donald Trump is the role model. Look at how workers are treated in the US. I think Boris Johnson will use Brexit as an excuse for every attack on workers’ rights in the book.”

O’Grady said Labour was right to challenge the idea that the election was just about Brexit. It was also, she added, about why people couldn’t get to see a doctor, why waiting times for hospital treatment were going up, why wages were stagnating and why workers’ rights were being eroded.

Labour had an alternative vision involving a safety net of rights from day one of employment, a £10 minimum wage for all workers, a ban on zero-hour contracts, freedom to organise, and a change in the balance of power between workers and employers.

Asked whether she was concerned that Labour’s minimum wage plans for all workers might cost jobs, O’Grady said: “There is plenty of headroom to improve minimum pay and we say people should get the rate for the job.

“Of course we want to see jobs protected but there is no evidence currently that significant increases in the minimum wage would harm jobs. There is evidence that the sweat shop model is too prevalent in Britain today. There are whole industries that could and should pay more.”