How hard can I prune a Hornbeam ?

Hi,

We have a Hornbeam in the garden that is 20+ years old and is currently about 3m high by 3m wide, with a depth of just under 2m.

To all intents and purposes it's been treated like a hedge, very light pruning a couple of times a year to give a really thick growth. Trouble is, it's now badly encroaching on the lawn and I'd really like to reduce the depth by roughly a third. I also intend to reduce the height by about 2 feet and maybe a slightly smaller amount off the width as well to give some other border plants a chance.

The thing I'm concerned about is will it be able to take such hard pruning ?

Many thanks for your advice.

Nick