The White House says President Barack Obama has spoken with Afghanistan's President Hamid Karzai to assure him that the change in war command does not affect U.S. policy on Afghanistan.
Obama informed Karzai in the call Wednesday of his decision toand to command the Afghanistan war effort.
The White House said Obama underscored that there was no change in the U.S. approach or commitment to Afghanistan.
White House officials said Karzai welcomed Petraeus' nomination and said he would support a successful transition.
McChrystal resigned after a magazine article carried disparaging remarks he and aides made about administration officials.
In the Rolling Stone article, McChrystal called the period last fall when the president was deciding whether to approve more troops "painful" and said the president appeared ready to hand him an "unsellable" position. McChrystal also said he was "betrayed" by Ambassador Karl Eikenberry, the man the White House chose to be his diplomatic partner in Afghanistan.
He accused Eikenberry of raising doubts about Karzai only to give himself cover in case the U.S. effort failed. "Now, if we fail, they can say 'I told you so,'" McChrystal told the magazine. And he was quoted mocking Vice President Joe Biden.
If not insubordination, the remarks - as well as even sharper commentary about Obama and his White House from several in McChrystal's inner circle - were at the least an extraordinary challenge from a military leader. The capital had not seen a similar public contretemps between a president and a top wartime commander since President Harry Truman stripped Gen. Douglas MacArthur of his command more than a half-century ago after disagreements over Korean war strategy.
Despite McChrystal's military achievements, he has a history of making waves. Last year, as Obama was weighing how to adjust Afghanistan policy, McChrystal spoke bluntly and publicly about his desire for more troops - earning a scolding from the president, who felt the general was trying to box him into a corner.