BRUSSELS — European Union officials said Friday that Google had submitted proposals aimed at ending a three-year antitrust case focused on its hugely popular online search service. But an industry group allied with companies that compete with Google immediately called for caution.

‘‘To be seen as a success, any settlement must include specific measures to restore competition and allow other parties to compete effectively on a level playing field,’’ David Wood, legal counsel for ICOMP, a group backed by Microsoft, said in a statement.