NEW YORK ( TheStreet) -- BP ( BP - Get Report) is a very dangerous stock, Jim Cramer said during his Stop Trading segment Friday on CNBC.

Cramer said the oil leak could very easily spew up to 100,000 barrels a day and if there is a hurricane in the Gulf Coast "the company is finished."

Cramer scoffed at those recommending buying BP's stock, saying they "have to have a reason." Cramer added that he is currently worried about Chevron ( CVX - Get Report) and Exxon Mobil ( XOM - Get Report) because of BP.

BP's CEO Tony Hayward testified in front of Congress yesterday, and Cramer said he learned a lot from the testimony. "It wasn't just 'let's dunk Hayword in a vat of BP oil,' though that's not something I would be against.

Instead, Cramer said he likes refineries like Suncor Energy ( SU - Get Report) and Tesoro ( TSO). But his favorite is Marathon Oil ( MRO - Get Report), which opened the newest refinery and is undervalued.

-- Reported by Jeanine Poggi in New York.

Follow TheStreet.com on Twitter and become a fan on Facebook.