This is just one of a series, but features a young Stephen Fry as Ivan, an equally young Blackadder colleague Tim McInnerny as the minstrel and Tony Cosmo as Abdul.
The words used in the song in the ad are obviously geared around the product, but use the tune and general theme of the original as written by Frank Crumit in 1941 (ish) using Percy French’s 1877 poem,
A number of references to the song and the ad call it Abdul la BulBul Emir (and have assorted spellings of Emir). This possibly comes from a mis-hearing of the proper title Abdullah BulBul Emir. I had alway known it as Abdul the BulBul Emir from having first heard some rather rude versions over the years prior to seeing the Whitbreadversion, but, anyway, here is the clip: