Labour has refused to share how many top-up debit card payments have been made to asylum seekers after it emerged that some used the funds to gamble.
Former Tory minister Steve Barclay accused the Home Office of trying to avoid scrutiny after his requests for the data were rejected three times.
Asylum Support Enablement Cards (Aspen cards) offer financial support for basic necessities like food, clothing and toiletries.
A claimant typically receives £49.18 each week via a Visa debit card, which enables users to withdraw cash as well as pay for in-store purchases.
Concerns have been raised, though, that migrants have been using the money to gamble.
Up to 6,537 asylum seekers have used the Government cards at least once in arcades and casinos, according to figures released under a freedom of information request.
Attempts to gamble online using the cards were made, but were blocked each time.
Mr Barclay, who Boris Johnson charged with overseeing efforts to tackle the small boats crisis, said: "Either the Home Office is intentionally trying to avoid scrutiny, or they simply don't know - either of which is damning.
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Some 80,000 asylum seekers use the Aspen cards
| REUTERS"There have been real concerns about the use of Asylum Support Enablement Cards, and the public has a right to know exactly how often taxpayers' money is being sent to them.
"They could be one of the many pull-factors that are fuelling the small boats crisis, which is even further out of control under Labour.
"The only way we can tackle it is through tougher measures, and to do this, we will need to be out of the European Convention on Human Rights."
Over the past six months, Mr Barclay has asked several parliamentary questions on the issue, trying to decipher information on the number of top-up payments made to Aspen cards.
On three occasions, the Home Office has refused to answer his questions.
Home Office minister Dame Angela Eagle refused to provide a figure, initially stating what the funds would cover.
She refused to include any more detail in the two follow-up questions from Mr Barclay.
Aspen cards are currently being used by 80,000 asylum seekers waiting on whether they have a valid claim to stay in the UK.
Steve Barclay had requests to the Home Office about migrant's gambling rejected three times
| PAThousands of asylum seekers are living in hotels at the taxpayers' expense.
The Home Office is able to track where the cards are used, but does not block payments for certain transactions.
Mr Barclay said that, given that the data must be held electronically in order to deliver the payments, there appeared to be little credible reason why the Home Office could hold onto the payment.
GB News has approached the Home Office for comment.