The “two-child policy” allows low-income families to claim child tax credits or universal credit for their first two children only.
New research from the Child Poverty Action Group (CPAG) has revealed that 160,000 families have had their income slashed by the two-child limit to-date.
The charity estimates that more than three million children could eventually be denied support by the benefit cap.
The figures show that across Lanarkshire’s seven Westminster constituencies more than 6500 families could be affected by not receiving benefits for over 22,300 children.
In both Motherwell and Wishaw, and Coatbridge, Chryston and Bellshill constituencies this equates to around 16 per cent of the children who live there.
Ms Adamson said: “Social security should be a safety net for all of us, but the two-child limit is having a devastating effect on families .
“All families are valuable and worthy of support, but this heartless policy turns people away when they most need it, and leaves children to grow up in hardship - which can have lifelong consequences for health and wellbeing.
“The Scottish Government has been left to pick up the pieces, investing over £125 million to mitigate callous welfare policies.
“In addition, it is introducing a Scottish Child Payment, without the two-child cap, this payment could go so much further.
“The next Prime Minister should make it a priority to tackle poverty and enable children to thrive, starting with reversing the two-child limit and horrendous ‘rape clause.’”