Economic guru Larry Kudlow gives President Donald Trump a “B” grade for his first six months in office and is optimistic about what the administration can accomplish before year’s end.

Trump “hasn’t succeeded in everything, he made some mistakes,” Kudlow, a Newsmax Finance Insider, told CNBC.

“To my way of thinking, he ended the war against business," said Kudlow,  who was an economic adviser to the Trump campaign. "He has ended the war against success and he has ended the war against fossil fuels. And he is looking out for America,” said Kudlow, a radio talk-show host and CNBC senior contributor.

The veteran financial guru and former Ronald Reagan adviser said not only would he give Trump a “pass” on a “pass/fail basis,” but “on a letter basis I'm going to give him a ‘B,’” he explained to CNBC.

“When he gets his tax cut, I'm going to move it to an ‘A,’” said Kudlow, who worked as Reagan’s budget deputy between 1981 and 1985. Kudlow predicted the president can achieve some sort of corporate tax reform by year's end.

Kudlow was an economics adviser to the presidential campaign of Trump, who ran on a pro-business platform of cutting taxes and regulation to create greater incentives to work and invest. 

During the campaign, Kudlow and economist Stephen Moore advised Trump on a plan of tax cuts and other reforms.

“Lower the corporate tax rate from 35 percent to 15 percent. Grant immediate expensing for new business investment. And establish a one-time 10 percent rate for the repatriation of offshore cash,” Kudlow recently said he and Moore recommended to senior White House officials last month. 

Meanwhile, Kudlow also praised Trump's other accomplishments, such as cutting regulation.

“His regulatory reductions have been terrific,"  said Kudlow, who was a key architect of Trump’s tax platform and an early supporter of the real-estate billionaire's campaign. 

"Particularly in energy. We're taking Russia out of the energy business in Europe because of energy exports,” said Kudlow, author of "JFK and the Reagan Revolution: A Secret History of American Prosperity," written with Brian Domitrovic and published by Portfolio.

To be sure, the Trump administration has withdrawn or delayed 860 proposed regulations in its first five months, the beginnings of a regulatory overhaul meant to bolster economic growth, the Associated Press reported.

Federal agencies have withdrawn 469 proposed regulations compared to a fall 2016 report when Barack Obama was president, according to figures from the White House budget office. This includes 19 regulations with an economic impact of $100 million or more.

Another 391 regulations have been delayed for further evaluation and consideration, the AP reported.

However, investors have been fretting over the recent obstacles to the Trump administration's grand vision to truly "Make America Great Again."

As a result, the U.S. dollar sank to its lowest in more than a year against key world currencies, Reuters reported. The dollar index fell 0.25 percent, falling to its lowest point since June 2016.

Investors have been worrying whether Trump's recent legislative setbacks and developments involving a probe into Russian meddling in the 2016 U.S. general election were threatening his domestic plans for tax cuts and infrastructure spending.

"Compounding the (weaker dollar) move is this latest news on the political front in the U.S. about the Russia investigation expanding to Trump’s business affairs,” said Alvise Marino, FX strategist at Credit Suisse in New York.

“This is on top of the fact that Senate has not been able to pass anything meaningful on the healthcare front."