The White House has not made a final decision on the deal, they said, but was believed to be leaning toward approval.
The bill moved toward approval today when the leaders of the small Komeito party said they would back it, assuring enough votes for passage.
The decision by the Italian and German companies pushed the merger one step forward toward formal approval.
But with the Senate now moving toward approval, the consequences could be quite different.
The move was seen as another step toward Congressional approval of the accord.
Mr. Lott began to sound as if he, too, was leaning toward approval, emphasizing how much progress had been made in recent weeks.
At the least, environmental advocacy groups say North Carolina's petition could help push the rule toward approval.
Once hailed as a breakthrough cancer treatment, interleukin-2 has been on a rocky road toward approval.
Other plans, like those for land tenure, are moving toward final approval.
Under terms of the deal, Bristol did not have to pay $800 million until the drug made certain progress toward regulatory approval.