Cross-border EU sales are currently VAT free, which means less administration and cash-flow tied up in VAT for businesses. Like anything, this can be abused and the VAT GAP is estimated at EUR168Billion in 2013.
This lays out the As-Is situation on cross-border VAT, there is no VAT charged on EU borders.
In future these changes are being considered. This would remove around 80% of the chance of VAT fraud occurring.
The EU commission is currently considering two options. All UK businesses trading into the EU will be affected by these. Depending on where we are with BREXIT will tell how much of these changes will be implemented by the UK prior to BREXIT.