Using of sum withinin group_concat

Let's say i have a table, Product. This contains several Products with different vatpercentages and vatprices:

Product

ArticleId | Price | VatPercentage | VatPrice
--------------------------------------------
    1       100     25.0000000000     25 
    2        80     25.0000000000     20 
    3        50      8.0000000000     4 
    4        70      8.0000000000     5.6 
    5        20           0           0
    0

Now i need to build strings using Group_concat and sum prices by vatpercentage where VatPrice is not 0 and price is not 0.

In this case i want the strings to look like this:

VatPercentage: 25% VatPrice: 45

VatPercentage: 8% 9.6

The code i've tried:

select 
group_concat('VatPercentage:' || 
CAST(VatPercentage as integer) || '% ' || 
'VatPrice:' SUM(VatPrice),'') 
FROM Product 
group by VatPercentage having count(Price) > 0

Fiddle

Thanks on forehand