GlaxoSmithKline on Saturday said it had rejected a 50-billion-pound offer from Unilever for its consumer goods arm, saying it “fundamentally undervalued” the business and its future prospects and that it would stick to its plan of spinning off the unit. Unilever confirmed the approach earlier on Saturday, saying the Glaxo unit would be a “strong strategic fit” as it continues to re-shape its portfolio spanning food, beauty, and home care brands. A deal of this size would be the biggest globally since the start of the pandemic, if it goes through. It could also transform Unilever into a formidable beauty and personal care purveyor, taking on the likes of Estee Lauder and L’Oreal, while for GSK, it could bring much needed relief from investor pressure that has been building over the past year. GSK said it had received three bids from Unilever, the latest on Dec. 20 comprising 41.7 billion …