The US National Institutes of Health (NIH) put a freeze today on all pending grant applications related to human embryonic stem cell research, although any ongoing stem cell projects funded by taxpayer-backed grants will be allowed to continue.

“Frankly, I was stunned,” said NIH director Francis Collins of yesterday’s court ruling. “The consequences of this decision are dramatic and far reaching.”

In the immediate term, many high scoring grants worth $15–20 million that were due to be funded will be put on hold; another 22 grants valued at $54 million scheduled for annual renewal next month have been frozen; and an additional 50 grants that were awaiting peer review are also being “pulled out of the stack,” Collins said in a press conference this afternoon. However, any money that has already gone out the door can continue to be spent.

The agency also canceled a meeting scheduled for today of the working group that evaluates whether to approve new human embryonic stem cell lines for federal funding.