Four health boards that are due to see their overall budget deficits triple in size will not be bailed out, the Welsh Government has said.
The boards are forecast to over spend by £151m this year.
In one case – Abertawe Bro Morgannwg University Health Board (ABMU) – the financial outlook is said to be “extremely challenging”.
The health board, which covers Swansea and Bridgend, said it was attempting to cut agency staff costs.
As well as ABMU there are overspends at Betsi Cadwaladr in north Wales, the Cardiff and Vale board and Hywel Dda in mid and west Wales.