I paid the earnest deposit for a subsale house recently and the property agent promised to process my mortgage and all, but with Bank A through his contact. 

I kept a good track of my financials, and I'm pretty sure I have better chance with Bank B or C, which offers better interest rate so I had asked the copy of booking form so that I may submit to other banks on my own, to keep my options open. But this agent refused to give me the copy, and insisted that I only take up mortgage from Bank A. My question is;

1) Am I obliged to take up mortgage from Bank A as proposed by the agent only? No other option?

This isnt the case during my first subsale purchase, where a different agent gave an option whether I submitted for mortgage on my own or through him.

And on another 2 occassions where I managed the purchase for my family members, the agent never forced a bank on us like this.

2) He sort of threaten to pull out from the process altogether when I asked for the copy the second time. I think the agent is obliged to produce a copy to me, after owner has signed, and I paid the earnest deposit, no?

What do I do now?