Writer and economist Robert Kiyosaki is warning that today’s economy is the “biggest bubble in world history,” and he is urging investors to offload all of their paper assets.

It has been a rough year for investors, as volatile financial markets have gradually declined, sending stocks and bonds falling and even broad benchmark Exchange Traded Funds going down deep into the red.

With assets hitting lows, and some insisting the worst central bank actions are behind us, some investors are hoping relief may be around the corner, and now might be a good time to go bargain hunting for risky assets that could pay off big. Kiyosaki, however, says the worst is yet to come, and buying in now would be a mistake.

He advises to “hold onto your money” as he shared his own personal strategy for what is coming, saying, “Many of you know I do not invest in equities, bonds, ETS or MFs. Please do not listen to what I’m going to say next: I would get out of paper assets.” He added the world economy “is not a market.”

What he does advocate for now is precious metals, saying their value tends to be more stable, and that may be a big advantage if the asset bubble pops.

He adds, “I’m not buying gold because I like gold, I’m buying gold because I don’t trust the Fed.” He added he prefers to purchase the metals directly for physical possession, as “real silver and gold coins,” and not in ETFs.