The PCS union represents some Job Centre staff
People looking for work have had their benefits stopped to meet government targets, the PCS union claims.
The union, which represents many job centre staff, said they had been under "enormous pressure" to stop claimants' Jobseeker's Allowance.
Some claimants said they had benefits withdrawn for "genuine mistakes" such as missing appointments.
The government says sanctions are a "last resort", and strongly denies the union's claim.
"Job centre staff are under enormous pressure to implement sanctions on unemployed people," PCS union north-east regional secretary Simon Elliot said.
"Staff are faced with the threat of sanctions themselves in the form of what they call performance improvement plans if they don't impose sanctions.
"If you look at the guidance for implementing the performance improvement plans it clearly states that it's a measure against targets."
'Begging for food'
David Taws from North Tyneside had his benefit suspended for forgetting an appointment.
He phoned to apologise but was told the Department for Work and Pensions (DWP) would need to be informed.
"The letter turned up on the 20th of December and I was literally sanctioned over Christmas," he said. "It was horrific - I had to go literally begging for food at a church hall."
Another man, who did not wish to be named, said his benefit was cut for a month in September.
"I explained that I was caring for my nana," he said. "I was up and down to the hospital with her. It totally slipped my mind. I phoned up and said I'm half an hour late for my appointment and they said, 'OK, we'll just put it as a miss'.
"I got a letter two weeks later saying I was sanctioned - for 28 days."
Mr Elliot said staff were being forced to carry out "politically motivated" objectives.
The DWP strongly denied there were any targets for the number of sanctions that Job Centre staff must hand out. It also said there was a right of appeal.
North Tyneside Council Conservative group leader Judith Wallace defended the use of sanctions to "stamp out the something-for-nothing culture".
She said: "If people are unemployed, and looking for work, clearly it is right that they should get benefits but, equally clearly, it's right that there should be conditions attached to those benefits."