President Obama said that an official response from the administration on what happened in the talks with Rep. Joe Sestak to drop out of Democratic Senate primary will come "shortly."

"I can assure the public that nothing improper took place," Obama said near the end of an hour long news conference devoted mostly to the BP oil spill in the Gulf of Mexico.

Bipartisan calls have increased for the White House and Sestak to disclose details of what happened between them. Sestak says that he was offered a top federal job to forgo a challenge to Sen. Arlen Specter of Pennsylvania, the administration's preferred candidate. Sestak has declined to go further, as has the White House.