NII Holdings’ proposed USD1.875 billion sale of Nextel Mexico to AT&T Inc cleared a major hurdle last week, winning approval from Judge Shelley Chapman in the United States Bankruptcy Court in Manhattan. However, Dow Jones reports that competing bidders still have until 17 March to up the ante and submit a rival offer. Anyone wishing to challenge AT&T ’s offer must put down a ‘good-faith deposit’ of USD32 million, which would go to AT&T if the telecoms giant is trumped in any subsequent auction. The report adds that AT&T would also be in line to have as much as USD10 million in deal-related expenses reimbursed should its offer prove unsuccessful. The auction for Nextel Mexico’s assets will take place on 20 March, with Judge Chapman set to make a final decision on 23 March. Outside of bankruptcy court, the sale also needs to win the approval of Mexican regulator Instituto Federal de Telecomunicaciones (Ifetel).