US tariffs on China won't fix the trade deficit, and neither will weakening the US dollar through interest rate cuts, International Monetary Fund economists said Wednesday.

In unusually blunt language, the blog post seemed targeted straight at President Donald Trump who has persistently demanded that the Federal Reserve cut interest rates to weaken the US dollar and juice the economy, while imposing round after round of tariffs on China to reduce deficit he describes as theft.

But the US policy moves are counterproductive, won't achieve the desired results, and will slow the global economy, IMF chief economist Gita Gopinath said.

"Higher bilateral tariffs are unlikely to reduce aggregate trade imbalances, as they mainly divert trade to other countries," Gopinath warned in a blog titled "Taming the Currency Hype," co-authored by fellow IMF researchers Gustavo Adler and Luis Cubeddu.

"Instead, they are likely to harm both domestic and global growth by sapping business confidence and investment and disrupting global supply chains, while raising costs for producers and consumers."

And any plans to weaken a country's own currency value "are cumbersome to implement and likely to be ineffective," they said, adding that pressure on the central bank will not achieve that goal either.

The authors warned that "one should not put too much stock in the view that easing monetary policy can weaken a country's currency enough to bring a lasting improvement in its trade balance."

"Monetary policy alone is unlikely to induce the large and persistent devaluations that are needed to bring that result ... especially within a 12-month period," they said.

With the US presidential election coming in November 2020, Trump is especially focused on the next 12 months.

'Bearing the burden'

Trump has slapped steep tariffs on $250 billion in Chinese, goods with the remaining $300 billion in imports targeted for new duties in two more rounds, September 1 and December 15.

With the IMF and others alerting that his trade war is slowing global growth, and as warning signs of a US recession have flashed red, Trump has doubled down on his attacks on the Federal Reserve and on China.

He and his advisors have been talking up the economy to counteract the increasing jitters on US financial markets.

At the same time, Trump has maintained his relentless attacks on the Fed, blaming Fed Chair Jerome Powell for failing to allow the economy to grow and for the strong US dollar.

In yet another Twitter outburst on Wednesday, Trump said of Powell, "Big U.S. growth if he does the right thing, BIG CUT - but don't count on him! So far he has called it wrong, and only let us down."

"Yesterday, 'highest Dollar in U.S.History.' No inflation. Wake up Federal Reserve. Such growth potential, almost like never before!"

Just last month, the IMF again downgraded its global growth forecast, and said the trade tensions make for a "precarious" 2020, in which tariffs threaten to exacerbate the slowdown of China's economy.

The IMF blog repeats much information released in separate reports, but highlights the key points and brings them together.

While economic theory states that a weaker currency tends to make a country's exports cheaper and more competitive, the IMF notes that many products are priced in US dollars on the global marketplace.

So in reality, it argued, "US importers and consumers are bearing the burden of the tariffs. The reason: the stronger US currency has had a minimal impact thus far on the dollar prices Chinese exporters receive because of dollar invoicing."