WASHINGTON, D.C.: The Pentagon’s number-two ranking official is stepping down from his post, officials said Thursday amid reports of strains between him and his boss, United States Defense Secretary Chuck Hagel. The surprise announcement came in a statement from Hagel, who said he had “reluctantly accepted” Ashton Carter’s decision to resign in a meeting on Thursday. “Ash has been an extraordinarily loyal and effective Deputy Secretary,” Hagel said. Carter was due to remain in the job for another two months to help the Pentagon as it grapples with a government shutdown and automatic budget cuts, officials said. Carter, who had served as the deputy from October 2011 under former defense secretary Leon Panetta, had reportedly enjoyed more autonomy under the previous Pentagon chief and had been on a short list to succeed Panetta in the top post.