The four consultants at the centre of the Waterford hospital morgue crisis warned in a second letter in March they may have to cancel their mortuary services to the hospital.
Consultant pathologists Prof Rob Landers, Dr Fergus MacSweeney, Dr Nigam Shah and Dr Christine Shilling wrote the second letter to South/South West hospital group chief executive Gerry O'Dwyer on March 26.
The letter was sent a day after Mr O'Dwyer responded to their initial concerns raised last autumn.
In the second letter, the consultants said the significant delay in responding to the issues they have raised amounts to an "inordinate delay" and "does not inspire confidence".
"Continuing failure to provide safe and dignified conditions will give us no option but to withdraw our post-morterm service from the current facility.
"The safety of our staff and public, as well as the dignity of the deceased, remain our only concerns. These matters must be resolved quickly and without further obfuscation or delay," they wrote.
Meanwhile, it has separately emerged that a senior HSE official wrote to the HSE's financial group the HSE Estates office last summer raising concerns about Waterford's morgue.
In a short letter sent on July 12, 2018, by assistant chief executive of the South/South West hospital group, Dr Gerard O'Callaghan said "at the request" of hospital management he visited the mortuary last year.
"The working conditions for the staff are not acceptable, nor is it a suitable environment for relatives of the deceased.
"I am aware that the development of a new mortuary has been a priority for hospital management for a number of years and they have included the current mortuary as a risk on their risk register. I believe it is now imperative that this development would be given priority by the HSE estates department," Dr O'Callaghan wrote.
The letters were released by Sinn Féin's Waterford TD David Cullinane on Friday.