1999 Honda Accord Reverse does engage properly.

I've got a UK spec 99 Honda Accord 4 Cylinder with the automatic transmission. The car drives great in all forward gears, everything seems normal. When I put the lever in reverse and don't touch the gas, the car will move very slowly with just the idle. When it's in reverse and I give it little gas the cars does nothing but revs and makes no weird noises or anything. Basically when it's in reverse I have to give it sudden moderate gas for the car to move at any normal reversing speed. If there isn't enough gas given then it will do nothing but rev so you have to shift back to park and then back to reverse again and give it more gas. What seems to be the problem and how do I fix this. Thank you for your help.