He said he and the others have met with a number of officials over there including Afghan President Karzai and General Stanley McChrystal.
Karzai, the senator says, denies he threatened to join the Taliban if he was pressured by his foreign backers.
Udall also said he remains skeptical about the war effort in Afghanistan but declined to talk in detail about his doubts until he returns home next week.
Of Karzai's alleged Taliban statement, Udall said, "He said his remark was misconstrued," Udall said. "I take him at his word."
Udall said the main thrust of the meeting with Karzai, Udall said was to stress the need for Karzai to "get rid of corruption" and to appoint competent people to government posts. In Afghanistan the president has the power to appoint officials all the way down to local levels.
He also said Karzai should address the American people, perhaps in the form of an in-depth interview with an American journalist, to talk about the partnership between the two countries.
Udall said the delegation met with several American military members, including two military security men aboard a plane who had been stationed at Holloman Air Base near Alamogordo. He also met with a Sgt. Reyes, helping with an agricultural project in Afghanistan, who has family in this state. These men all received gifts of pinon-flavored coffee and red and green chile jerky.
In Udall's delegation are Sens. John Ensign, R-Nev.; Scott Brown, R-Mass.; and Tom Carper, D-Del.; as well as Rep. Rob Wittman, R-Va.
Udall said he's heading home on Sunday.