The call comes alongside the launch of a strategy to improve services for some of the country's sickest children and their families.
The government announced an extra£20m in grant funding for children's hospices and hospice care at home up to 2011.
But campaigners stressed a need for wider investment in the statutory and voluntary sectors, across health, education and social care.
Care services minister Ivan Lewis said he expected PCTs to use increases in baseline funding to invest in children's palliative care.
The Better Care: Better Lives document was drawn up in response to a government-commissioned independent review of children's palliative care, which revealed huge variations in availability of services and funding.
"It is an absolutely excellent document," said Association for Children's Palliative Care chief executive Lizzie Chambers.
But she predicted "a long, hard slog ahead" to ensure the strategy was fully implemented.
Association of Children's Hospices chief executive Barbara Gelb said a big problem was lack of understanding among commissioners of what children's palliative care involved.
The strategy places a new expectation on trusts and strategic health authorities to establish local and regional children's palliative care networks, which bring together commissioners, clinicians, and providers from all sectors.
It also says families should have access to round-the-clock advice and support from community teams to help cut unplanned hospital admissions.