>> the white house pushing back on investigations by house democrats. the strategy could involve withholding documents. north korea has begun rebuilding part of a long-range missile test facility. work began right around the summit between the president and kim jong-un. and a new drug has been approved to treat severe depression. major news for millions who haven't been helped by other anti-depressants. good morning, everyone. welcome to "early start." i'm dave briggs. >> good morning, i'm christine romans. it's wednesday, march 6th. for the second time in two weeks we're learning that the president overruled security officials on personal grounds. three sources tell cnn president trump pressured top aides to grant a security clearance to first daughter and senior aide ivanka trump. now ivanka contradicting that to abc news three weeks ago. >> president had no involvement pertaining to my clearance and my husband's clearance.