Two months after India dropped local-trial rules for Covid-19 vaccines approved by developed countries, not a single dose has arrived as New Delhi dithers over legal protection sought by companies like Pfizer and Moderna.

The United States has in recent weeks donated millions of vaccine doses to countries such as Bangladesh, Bhutan and South Korea. Supplies to India, however, are stuck pending the conclusion of some "legal requirements", according to the global Covax vaccine platform through which such doses are routed...