The Pakistani diaspora kind of captured Labour Party under the last leader. There are two aspects to this:
The Pakistani diaspora overwhelmingly votes for Labour making it an effective vote chunk compared to Indian diaspora that votes for both parties and is, therefore, more diffused
The Pakistani diaspora is geographically more concentrated than their Indian counterparts.
However, the recently the labour party's actions led to the Indian community jettisoning the party and moving to conservative. This is their attempt to keep the votes intact.
I have to say though at the end of the day, even if both conservative and labour said that Kashmir is an international issue or even that Kashmir should be Pakistani, I don't see that making an iota of difference to India on the ground. India is now economically strong and globally meshed enough that it doesn't matter what any other country says.
@waz , I am curious why Pakistanis still continue to seek international support on this. What's do they think will happen if Britain or any other country voices that Kashmir is an international issue?