The threat of oil's supply is what continues to move its price higher and higher, Jim Cramer said on his

"RealMoney" radio show Tuesday.

Although there are plenty of people calling for alternatives to oil, Cramer doesn't believe that there is even one alternative that can take oil's place during his lifetime.

People are never going to be able to build enough windmills, and coal is too dirty. Therefore, "we need to find new oil," he said.

Chevron

(CVX) - Get Report

and

Devon Energy

(DVN) - Get Report

, which have both been testing oil reserves in the Gulf of Mexico, have "nailed" a major oil discovery there, Cramer said.

Devon Energy, which he owns for his charitable trust

Action Alerts PLUS, is up eight points, and Chevron is up two.

"The way for oil companies to move their stocks up is to find oil," Cramer said. "These finds will put a ceiling on oil."

There is a new pattern in the market, which is that "the Japanese are back," and "they are in acquisition mode," Cramer told listeners.

Asahi Tec

, a Japanese auto-parts manufacturer, on Friday agreed to acquire

Metaldyne

, a U.S. competitor that makes engine parts, for $200 million, Cramer said.

Back in the late 1980s and early 1990s, "hardly a week went by when the Japanese didn't buy one of our companies, particularly our high-tech companies," he said. Then the Japanese economy fell apart.

But Cramer called the Asahi Tec/Metaldyne news "a radical shift by the Japanese."

"They will come back," he said.

To see the most recent edition of The RealMoney Radio Recap in its entirety, please click here. This recap is published every day around 3 p.m. ET.

At the time of publication, Cramer was long Devon Energy.

Jim Cramer is a director and co-founder of TheStreet.com. He contributes daily market commentary for TheStreet.com's sites and serves as an adviser to the company's CEO. Outside contributing columnists for TheStreet.com and RealMoney.com, including Cramer, may, from time to time, write about stocks in which they have a position. In such cases, appropriate disclosure is made. To see his personal portfolio and find out what trades Cramer will make before he makes them, sign up for

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