Defra detailed proposals and invited views on managing risks from the fungal pathogens at a meeting in Cornwall on 29 July.
A Defra representative said: "Any policy proposal recommended will be subject to the relevant financial mechanisms within departments and devolved administrations, which may include consideration of opportunities to share costs with stakeholders."
Hampshire grower John Middleton said: "Defra spends £2m a year already and is making no impact. And it can multiply that cost by several times for the cost to growers - a cost it admits it doesn't know."
Meanwhile, Swansea council revealed it had spent £800,000 dealing with the disease and may need to spend £1m more.
- Stakeholders should call Margaret O'Donnell on 01904 455182.
Since the first detection of P. ramorum in 2002 and P. kernoviae in 2003, Defra and the Forestry Commission have spent £2m a year on containment and eradication. Under an approach that slows the spread gradually it will cost £32.2m in the next 20 years. Under a fast eradication approach it will cost £46m over 20 years.