Michael Bloomberg, in a blistering op-ed for his namesake media company, eviscerated President Donald Trump for the federal government shutdown and called the budget standoff a “dumb” way to demand border wall funding.

The former New York mayor’s column, published on Sunday, said the partial shutdown of the U.S. government shows Trump’s administration is unraveling.

Bloomberg wrote that his major concerns include the potential for an economic nosedive triggered by what he described as Trump’s devil-may-care style of leadership.

“With other countries pleading for sanity and institutions such as the International Monetary Fund and World Trade Organization warning of severe consequences if trade sanctions get out of hand, talk of a looming recession is growing,” he said. “Yet the president seems determined to make matters worse — and to hell with the economic consequences.”

Bloomberg pointed to last week’s stock market plunge as another sign that “Trump’s recklessly emotional and senselessly chaotic approach to the job” has a real impact.

“At the halfway mark of this terrible presidency, one has to wonder how much more the country can take,” he added.

The only solution, Bloomberg said, was for the GOP to stand up to Trump.

“Unless something changes — unless, in particular, Republicans in Congress start showing some spine — two more years might be enough to test whether we can sustain Trump’s model of bad government. This past week, we got a glimpse of what the beginning of the collapse may look like — and what it may ultimately cost us.”

Bloomberg, a Democrat, has openly flirted with a 2020 presidential run.