Charlie shailer

Hi, apologies if my question has already been answered but I just want to double check my situation. I have an e-commerce business which I source my products from china. I currently hold stock in the UK and ship to customers in the UK and the USA. Current turnover is at £90k a year. Revenue is roughly 50/50 split from UK and USA. I basically don’t want to go VAT registered as my profit margins will go from 20% to roughly 0. But I want to grow my business. If I keep my UK revenue under £90k, will I be able to stay away from being VAT registered? Or does the USA revenue count towards VAT threshold. If the answer is USA sales count towards VAT threshold because I ship from UK. What if I get stock sent from china directly to USA warehouse? Thanks!