Istanbul - The United States' ambassador to Turkey has again denied allegations his country was involved in last month's failed coup attempt, Turkish media reported on Saturday.US ambassador John Bass said in remarks published in English daily Hurriyet Daily News: "I just want to say again, as I've said before and as we've said from Washington, the United States government did not plan, direct, support or have any advance knowledge of any of the illegal activities that occurred the night of July 15 and into July 16. Full stop." He added that he was "deeply disturbed and offended by the accusations" targeting his country.The July 15 military action blamed by Ankara on US-based Muslim cleric Fethullah Gulen has rattled Turkey's relations with the United States and the European Union.President Recep Tayyip Erdogan has accused the West of supporting the plotters and warned Washington that relations would suffer if it failed to extradite Pennyslvania-based Gulen. Erdogan has also accused the US of hiding and sheltering the preacher and described the failed military action as a "scenario written from outside" in an allusion to foreign involvement.Claims of CIA involvementShortly after the coup attempt, Labour Minister Suleyman Soylu went even further to say "the United States is behind the coup".And this week, Turkey's former army chief, Ilker Basbug, claimed that the US Central Intelligence Agency (CIA) was also behind it. "Frankly, if we would have had knowledge we would have told the Turkish government about it immediately," Bass said.He said the US wants to see a "strong, prosperous, democratic, confident Turkey."Anyone who thinks that the United States somehow profits from Turkey being divided and destabilised I think is misreading history to a profound degree."Three days after the failed coup, Bass rebutted claims his country somehow supported the putsch."This is categorically untrue and such speculation is harmful to the decades-long friendship between two great nations," he said in a statement on the embassy website.