Vale SA has shelved plans for an initial public offering (IPO), or stock-market listing, of its critical minerals unit, Vale Base Metals, amid political pushback in Brazil over potentially losing control of strategic mining assets. The IPO is on hold indefinitely but could be revived in the future, The Globe and Mail reported, citing sources. Vale Base Metals Chief Executive Officer Shaun Usmar said in March on BNN Bloomberg Television that the company was preparing the business for a potential IPO by midyear. Vale did not immediately respond to a Reuters request for comment outside regular business hours.