President Trump dramatically escalated his pressure on the Federal Reserve to cut interest rates later this month, attacking for the first time the Federal Reserve Bank of New York in his months-long criticism of the central bank.

Trump has sharply criticized the Fed for almost a year, saying its decision to raise interest rates four times last year squelched economic growth and prevented the stock market from rallying.

“We are in a World competition, & winning big . . . but it is no thanks to the Federal Reserve,” Trump wrote in a series of Twitter posts Friday morning. “Had they not acted so fast and ‘so much,’ we would be doing even better than we are doing right now. This is our chance to build unparalleled wealth and success for the U.S., GROWTH, which would greatly reduce % debt. Don’t blow it!”

Many economists dispute his views, warning that low interest rates at this point in the business cycle could create dangerous bubbles that damage the economy with little notice. But the Fed appears almost certain to cut interest rates later this month, taking an unusual step when the unemployment rate is below 4 percent.

One reason Trump has continued to exert pressure on the Fed is a growing fear that the economy could be slowing, a predicament that could cause major political headaches for Republicans heading into 2020.

In explaining their openness to cutting rates this year, Fed officials have cited slowing global growth, low inflation and uncertainty caused by Trump’s trade war as the principle reasons why they would make the step.

Fed leaders are set to announce what they will do with the interest rate on July 31. Wall Street widely expects a cut, but there is heavy debate about whether it will be a modest reduction or a more sizable one.

The benchmark U.S. interest rate is currently in a range of 2.25 to 2.5 percent, a low level by historical standards but the highest rate since the Great Recession rocked the global economy a decade ago.

Few presidents in modern history have publicly jawboned the central bank as much as Trump, and it has raised concerns about politicization and the prospect that Trump has eroded the central bank’s independence. But Trump and top aides have brushed the criticism aside and continued their blistering attacks.

The upshot for Americans and businesses is that the cost of borrowing money is likely to fall in the coming months, which White House officials hope will lead to more business investment and a higher stock market.

It is one of many ways Trump is trying to juice the economy heading into the 2020 elections. Trump has also sought major tax cuts and spending increases as a way to boost growth, even while driving up the deficit. And he has pressured foreign leaders to lower oil prices in a way that he believes will help the U.S. economy.

Aside from his constant verbal attacks, Trump has tried to transform the Fed in numerous ways. He has appointed all but one of its current five governors, and he has announced intentions to nominate two more, after four others were unofficially rejected by the Senate.

The stock market was mostly flat last year, with investors spooked about various trade wars launched by Trump against China and other countries. The stock market has rallied for much of 2019 setting fresh records this month, in part driven by comments from the Fed that it will stop raising interest rates and multiple hints that it plans to lower the cost of borrowing soon.

Trump has taken credit for the stock market increase in recent weeks, but he has only ramped up his pressure on the Fed not to reverse course. That appeared to be the purpose of his criticism aimed at Federal Reserve Bank of New York President John Williams, in part because some thought the Fed official was showing signs of waffling.

Williams, who is considered one of the Fed’s most prominent voices, appeared to strongly suggest that the central bank would make a larger-than-expected cut in July, a sentiment that boosted the stock market.

“When you only have so much stimulus at your disposal, it pays to act quickly to lower rates at the first sign of economic distress,” Williams said Thursday in a speech at the Central Bank Research Association.

The New York Fed tried to walk back the remarks later in the day with a spokesperson saying that Williams was referring to what the right course of action is generally, not for the end of this month.

In a Twitter post, Trump wrote “I like New York Fed President John Williams first statement much better than his second,” he wrote. “His first statement is 100% correct in that the Fed ‘raised’ far too fast & too early.”

There is an active debate on Wall Street about whether the Fed will do a modest quarter-point interest rate cut or a more substantial 50 point reduction. Trump is signaling his strong preference for the bigger cut, but Wall Street currently gives that a 41 percent likelihood, according to the CME FedWatch Tool where investors make predictions about what the Fed will do.

Up until this point, Trump had leveled almost all of his Fed criticism at the central bank’s chairman, Jerome H. Powell, someone Trump nominated for the job in late 2017. Trump has asked aides whether he has the power to remove Powell from the Fed, and has frequently refused to express confidence in Powell’s stewardship of the central bank.

Powell has said he works independently of political interference, but Trump has sought to install political loyalists on the central bank in recent months in an effort that some lawmakers worried would have eroded the institution’s economic integrity.

Trump’s recent demands for low interest rates are a marked departure from the exact opposite viewpoint he used to hold when it came to the central bank. In 2011, Trump attacked the Fed, then led by chairman Ben Bernanke, for keeping interest rates low.

“The Fed’s reckless policies of low interest and flooding the market with dollars needs to be stopped or we will face record inflation,” Trump wrote that September.