CNBC’s Jim Cramer recommended that long-term investors put some cash to work in the broad market after Wall Street’s steep declines Tuesday.

Specifically, the “Mad Money” host suggested looking to an index fund that tracks the S&P 500, which he has long contended should be a core piece of portfolios.

“Given that it’s a good idea to keep some money in an S&P 500 index fund for your retirement, you have my blessing tomorrow morning to commit some capital,” Cramer said after the S&P 500 fell 1.9%, Dow Jones Industrial Average dropped 1.86% and tech-heavy Nasdaq lost 1.6%.

“It’s too early to buy hand over fist, but too late to sell at this point,” Cramer added.

The major U.S. equity averages slumped Tuesday as investors weighed the latest news on the newly detected Covid omicron variant, as well as Federal Reserve Chairman Jerome Powell’s comments about possibly speeding up the central bank’s reduction in asset purchases.

Cramer suggested Monday investors wait for the first omicron case to be confirmed in the U.S. before doing some buying. However, he said his roadmap has changed slightly, given how broad-based the selling was Tuesday.

“At one point today we had nine-to-one selling to buy,” Cramer said. “That’s a hallowed ratio where the late Mark Haines, a legendary CNBC anchor and good friend of mine, would always tell you that you had to do some buying.”

Cramer stressed that investors should not go “too deep into this market yet,” meaning do not go all out on buying individual stocks. Instead, he said he’s advising long-term investors to put a fraction of their cash on hand to work.

“The rest needs to be put to work in stages after we start getting battered by omicron cases here in America if something really goes wrong,” he said. “I’d say call it one-quarter of your money [Wednesday], one quarter the day omicron hits our shores, and then the next half over the following few days. This is the kind of thinking I think for people with IRAs, 401(k)s, this is your chance if you haven’t done it yet.”

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