The cost of disability benefits specifically is projected to surge almost a third in the next four to five years, according to the Institute for Fiscal Studies.
It predicted the Department for Work and Pensions (DWP) would spend £63bn by 2028-29, a jump from £48bn for 2023-24.
“I want to see those costs coming down, because I want to have people able to work, to get on in their work, which is good for them," Kendall told BBC News in an exclusive interview.
She indicated some people will lose their benefits, saying the "benefit system can have a real impact on whether you incentivise or disincentivise work".
Kendall praised projects in Leicester and at the Maudsley Hospital in Camberwell, in south-east London, which offered employment support - such as training on CV writing and interviews - to people with serious mental health conditions, including on hospital wards.
"The results of getting people into work have been dramatic, and the evidence clearly shows that it is better for their mental health," she said.
However, disability rights campaigner Erhardt said he would like to see the evidence of the trials.
"It is hugely inappropriate to be considering subjecting people who experience mental ill-health and distress to a CV check-up," he said.
Minesh Patel, associate director of policy and campaigns at Mind, added: “We welcome this much-needed spotlight on mental health hospitals [but] we’re still waiting to see the full details of the scheme and results of the trials.
“Right now, too many people with the most serious mental health problems are left more traumatised by their stay in hospital. If we want people to join or rejoin the workforce, they need safe and compassionate care that helps them truly get better."The move by the government comes as figures suggest benefits will rise by 1.7% next April. September's inflation data is normally used to calculate how much many benefits go up by.
