article_snippet.sent: For the negotiators, this week was marked by a marathon run of meetings, sometimes lasting throughout the night.
article_snippet.sent: There was a sense of urgency, both before and after the initial March 31 deadline passed, to reach a final understanding so the foreign ministers could leave Switzerland ahead of other time commitments, not to mention the Easter holiday.
article_snippet.sent: The process was further complicated by restrictions on the flight crew for Kerry's plane, which could stay on standby at the airport for only a limited number of hours in a given time period.
article_snippet.sent: We'd get close, We kept on changing the plane schedule," a senior administration official told reporters.
article_snippet.sent: On the evening a final understanding was finally announced, the window had already lapsed, requiring Kerry and Kerry team to depart at 3 a.m. Friday.
article_snippet.sent: There were "many moments (throughout the negotiations) when We thought We'd call it a day, call it a night, decide We'd gone as far as We could go," said the official, who briefed reporters on Kerry's plane.
article_snippet.sent: But perhaps the most difficult night for negotiators was between Wednesday and Thursday, just before the final sticking points were resolved for a deal.
article_snippet.sent: It was a very, very intense," said " a senior administration official.
article_snippet.sent: It went from 9 -- about 9 in the evening until 6 in the morning when we all decided we all'd reached a couple of roadblocks, didn't know whether we all'd be able to get past a couple of roadblocks, and we all were all utterly, utterly exhausted."
article_snippet.sent: So we all went to sleep by maybe 7, got up again and started again about 9:30, and engaged on what we all thought were the really final issues," " a senior administration official added.
article_snippet.sent: The eight-day-long diplomatic event had hit The eight-day-long diplomatic event crescendo before finally subsiding.