Its hell - been there! we found it was a several stage approach.
At least with a kid over 2 you stand a better chance of explaing to them that no they can't have milk at night.
You pick a week when you and DH/P can do some night shifts and also get some rest during the day.
On the first day, feed DS wheatever he likes all day long, obviuosly limit sweeter things later on in case of a sugar buzz but try not to restrict his choice in any other way - the aim is to get him as full up as possible of solid food. Let him eat wherever he wants as well, in his pram in front of the TV etc.
Use any trick you can, and give either a breast or bottle feed last thing before bedtime, lights off and all quiet.
as part of the bedtime routine explain to DS that he can't have milk during the night now - you'll know what would work best for him whether beign told he is a 'big boy' or whatever.
Promise a treat if he gets through the night with no milk/food - the treat often works best if its more time with you or dad or both doing something he enjoys. That way you can also link no milk = less tired mummy to play with you.
He is probably old enough for a simple star chart too - so 1 star = no milk, maybe a gold star if no waking mummy or daddy up at all.
Agree a wakeup time - I'd suggest a 6am feed if he has been feeding alot at night.
Then you have to grit your teeth and stick at it.
Is it just the milk feeds you want to stop or do you want him in his own bed? thats the other decision. If you are fine with co sleeping but are BFing you may find you ahve to sleep in a spare room otherwise in the ngiht he will smell the milk/see you and if he is right next to you he will feed - if its his dad its very different.
If you also want him in his own bed you may need to spend a fair proportion of the first few nights either in his room with him or sitting outside his door.
A healthy 2 yr old won't starve overnight, hard as it is if you have offered plenty of food throughout the day you have to be the strong one and see it through for at least one night - hopefully he will then be ravenous for breakfast - again make it his fav foods and relax the rules a bit.
Good luck