Two support organisations for local voluntary organisations have urged the government to preserve the total amount of lottery money going to the third sector.
The proposals are expected be enacted in September.
Navca and the DSC said that any money redistributed from the BLF to other funds should continue to focus on supporting local organisations.
The two organisations also called on the department to rethink a 5 per cent cap on lottery administration costs, which they said would lead to fewer, larger grants, which would harm smaller organisations.
Debra Allcock Tyler, chief executive of the DSC, said: "With public spending cuts threatening local authority grants, and trusts and foundations suffering from the recession, lottery grants may become more important than ever for charities.
"It's vital that changes to the way the lottery distributes money do not reduce the amount of money available to charities, or make it less accessible."
A spokeswoman for the DCMS said the Big Lottery Fund would have more funding after the proposed changes because of increased levels of lottery income and the ending of transfers to the Olympics.
"The Big Lottery Fund isn’t the only lottery distributor that funds the voluntary and community sector," she said.
"For example, around 70 per cent of the Heritage Lottery Fund’s grants and 60 per cent of those from Arts Council England go to voluntary and community sector organisations."