A senior White House official has resigned days after he was criticised for allegedly playing down global warming in US government documents.
The White House said Philip Cooney's sudden departure was totally unrelated to the allegations.
He was chief of staff at the White House Council on Environmental Quality.
Critics say his alterations cast doubt on the link between greenhouse gas emissions and climate change, accepted by most scientists.
"[Mr Cooney] had accumulated many weeks on leave, and so he decided to resign and take the summer off to spend some time with his family," presidential spokeswoman Erin Healy told AFP news agency.
The case was first brought to light by the New York Times, which said it had obtained the documents edited by Mr Cooney from a non-profit group granting legal assistance to government whistleblowers.
The White House says the changes made by Mr Cooney, a former energy industry lobbyist with no scientific background, were part of a normal review process.