AML check?

Hello. FTB here. We are in the process of buying house. We have moved to UK exactly an year ago. We were living in middle east for 15 years before coming to UK. My spouse and I are both working. We had quite a bunch in savings. And we are using those to pay as deposit for our house.

Offer is accepted, mortgage advisor is finalised, lawyer is already working, did the preliminary surveys and all. Now we are at the stage of AML checks.

As newbie here, my question is, what and how this process works? What do they check? When should i be worried? Did you face problem for AML checks?

Thank you