Congressional Democrats are demanding a full accounting of White House chief of staff John Sununu's use of military jets for personal and political travel, including ski trips and frequent hops back to his New Hampshire home.

The White House on Sunday defended Sununu's travel arrangements, saying he cannot take airline flights because President Bush needs to be able to reach him at all times. A spokesman said the government was reimbursed "whenever appropriate" for the trips, which cost taxpayers more than a half-million dollars.The Washington Post and U.S. News & World Report reported over the weekend that Sununu has taken more than 60 trips over the past 27 months on corporate-type military jetliners, almost half of them to New England, as well as such vacation spots as Vail and Aspen, Colo.

The trips included both official business and personal and political travel, the accounts said.

White House Press Secretary Marlin Fitzwater said Monday, "He's reimbursed for all of his trips on a continuing basis as he's taken them." Asked whether the White House planned to review the policy of having Sununu fly only on military planes, Fitzwater said, "Not to my knowledge."

Asked to release records of Sununu's trip, Fitzwater said, "We'll have to talk to the governor when he gets back" from a weekend trip to New Hampshire, where he spoke Friday night to the Manchester, N.H., Republican Committee.

Commercial air fares would cover only a fraction of the cost of flying on a C-20 business jet. The Air Force lists the C-20's hourly operating rate at $3,945, not counting the salaries of the five-member crew.