Government aid requests from General Motors Corp and Chrysler may rise considerably, a top adviser to President Barack Obama's auto task force said in a Bloomberg Television interview.

The current aid request from the two automakers depends on them achieving plans that are somewhat ambitious, Steven Rattner said in the interview.

Like all management teams they tend to take a reasonably, slightly perhaps, optimistic view of their business. So it could be more, I can't rule that out.

Chrysler, about 80 percent controlled by Cerberus Capital Management , and GM have received $17.4 billion of U.S. government emergency loans. They have sought billions of additional aid in requests submitted in mid February.

Rattner also told Bloomberg that Chrysler's proposed alliance with Italy's Fiat SpA was worthy of consideration. He also said Chrysler's numbers showed it barely making it as a stand-alone company, though the task force has not made a determination of whether it could exist on a stand-alone basis.

Rattner said he may set a deadline for the United Auto Workers, GM bondholders and other parties to reach agreements. He also said in the interview that GM bondholders need to become part of this in a constructive way.

(Reporting by David Bailey, editing by Matthew Lewis)