I'd really appreciate anyone's advice on my unfriendly male mini lops. 

I'll give you a little back ground on them: they're from the same litter so are biological brothers. I've had them for nearly 3 months now and then coming up to 5months old. They were playful and friendly to begin with but over the past couple of weeks have become quite withdrawn and seem to run away whenever I try to stroke or play with them. They're eating and drinking as normal and have lots of time out of their cage to run around. Am I doing something wrong or missing something really obvious. I just want my playful happy bunnies back.

What do you mean by withdrawn?

I think part of this behavior is perfectly normal rabbit behavior. I do think you need to make arrangements to get them neutered at this point as well, if you haven't already.

They used to like to sit with us and be in the same room as us but now they would rather sit in their cage or in the corner of a room and don't seem to like being stroked at all...

We do have them booked in to be neutered in 2weeks time.

It sounds to me like they are just comfortable in their surroundings. I have a free roam rabbit who has access to all areas of my home (mostly) and he's very friendly but he likes to only be petted on his own terms.

I would suggest that if you just let them come up to you that eventually they will come allow you to pet them again.

It's not that your rabbits are being unfriendly - they are just wanting their own space...kind of like teenagers.

I agree with Sarita. Let them come to you, and have treats ready for when they do come to see you.

Thank you! That's really helpful, I do try to tempt them with veg and the odd treat but i was worried there was something wrong. Good to know all is well :-)

Agreed! Bribery is the best method
I make sure there is always a snac on the table and if they jump up in the couch with me, there will always be a prize.