There is enough room: you break off the plastic washer first.
The bolts are secured with high strength loctite and apparently if you can't manually break the loctite bond you have to use a heat gun. This is Brompton's way of making absolutely sure that the bolts don't loosen when riding, but since I keep an eager eye on my bike I've used low strength loctite for the last couple of years and not had any problems.