The Government's Brexit Bill will be the "biggest job-killing act in Welsh economic history", a Plaid Cymru MP has claimed.
Jonathan Edwards urged ministers to honour a Leave pledge made during the EU referendum campaign to maintain current EU funding in Wales after Brexit.
He said the Government's European Union (Notification of Withdrawal) Bill which would empower the Prime Minister to kick off formal divorce proceedings with Brussels "pays no regard" to promises made in the run-up to June 23 last year.
Mr Edwards sought to make the case for a Plaid Cymru-led amendment to the Bill which would require the Government to present a report to the Welsh Assembly spelling out the impact of Brexit on Welsh finances.
That report would allow the Assembly to scrutinise the pledge to maintain funding.
Plaid's amendment was defeated by 330 votes to 267, majority 63.
Mr Edwards said voters in Wales had been "swayed by a torrent of false promises" ahead of the referendum and that Plaid's amendment would "hold the Brexiteers' feet to the fire."
Labour's Stephen Doughty backed the move.
Mr Edwards said the Government's Brexit white paper, published last Thursday, had been a "complete whitewash" on the issue of funding pledges.