Pear rust?

I have multiple pillar fruit trees however my pear column has pear rust, what is the best way to remove it without damaging the tree and stopping it transfer to my other trees, they are all potted
Thanks guys

 

I used Westland Plant Rescue to get rid of scab on an apple tree and I think it would work on rust. I've a suspicion it's on the 'withdrawn list' but you might be able to get hold of some. The active chemical in it is Difenoconazole which as far as I know in now only available to commercial growers.