Port Arthur oil refinery (L), Saudi King Salman (R)

Despite U.S. President Donald Trump's previous calls to halt all imports of Saudi oil, the kingdom has taken 100 percent control of the largest oil refinery in the U.S – also the largest in the Americas. 

The takeover of the Port Arthur refinery in Texas, which officially happened on Monday, has been in the works since an announcement last year, according to CNN Money

Saudi Aramco, the kingdom's state-owned oil giant, previously owned 50 percent of the facility. With the complete takeover, Saudi Arabia will significantly increase its presence in the U.S. oil market.

Trump previously suggested he would block Saudi oil from the U.S.

During his presidential campaign, Trump suggested that he would halt all imports of Saudi oil.

"We will accomplish complete American energy independence," Trump said during a campaign speech in May.

"Imagine a world in which our foes, and the oil cartels, can no longer use energy as a weapon," he said.

But with the takeover of the Texas refinery, the kingdom will ensure greater access to the U.S. oil market. The facility already processes some 600,000 barrels a day. With full control, Aramco can send more of its own crude to be processed.

And that's not all. 

The deal also gives Aramco full ownership of 24 distribution terminals. Furthermore, the Saudi oil giant has gained exclusive rights to sell Shell-branded gasoline and diesel (Shell is a British–Dutch multinational oil and gas company) in the entirety of five states, as well as the eastern half of Texas and the majority of Florida.

Of course, Saudi Arabia is already the second largest supplier of crude oil to the U.S., just behind Canada. The amount of crude imported from the kingdom has already increased since Trump took office. Some 1.3 million barrels were imported by the U.S. in February, 32 percent higher than the same month last year.

Trump with Saudi Deputy Crown Prince Mohammed bin Salman

Saudi Aramco is going public next year

Expanding in the U.S. market is especially important as Saudi Aramco plans to go public in 2018, trading a 5 percent stake in the company.

As the world's largest oil and gas company, the kingdom hopes the IPO will rake in a whopping $100 billion, valuing Aramco at some $2 trillion.