Thanks for the lead! I hope you find the name. We have very little information on contemporary Belgian potters, there's only one or two websites dealing with Belgian work.
This is the mark of the "New Milford Pottery Company/Wannopee Pottery - 1886 - 1903 They traded as New Milford up until 1890 and made white granite, cream coloured and semi-porcelain table and toilet wares until 1890 when they changed their name to Wannopee and started making pottery art wares like yours. So your pot was made between 1890 and 1903. Hope this helps you chariot