Mike Denis, director of information at South London & Maudsley NHS Trust, also questioned the extent to which other mental health communities will be in a position to benefit from electronic booking systems and the planned national data spine without first implementing appropriate infrastructure systems locally.
Key components of the national programme are a data spine of summarised medical records and a national system to enable doctors to book hospital appointments electronically.
Denis said his trust was fully committed to the national programme but there was uncertainty and confusion about the funds that will be required locally.
"It is unclear what local funds will be required to implement the core services contracted through CCA [Capital Care Alliance]. I am seeking urgent clarification." CCA is the BT-led consortium that won a £996m contract in December as the local service provider for London.
Referring to an historic under-investment in IT by mental health organisations, he also said his trust did not yet have integrated systems to feed useful data into the national applications.
Meanwhile, trusts across England will be making decisions over the next two months about how much they can afford to spend on implementing national systems.
Yvonne Baker, head of PCT IM&T partnership service in Avon, said the next two months would be critical.
In a paper dated 28 January on the implications of the national programme, Baker said, "We have to balance the potential benefits of the national programme in supporting new ways of working across the community, with the costs of implementing new systems."
National funding would only cover part of the overall programme, she said. "It will not cover training, data cleansing, support, and change management costs, even for the nationally funded applications."
Last year there were financial shortages in her area, but Baker was hopeful that money would be found to participate in the national programme. "By 25 March we should be clear about what we are going to do, and about what the IM&T agenda in this part of the world will be for some time to come," she said.