(Adds details of planned meeting with U.S. defense companies)
WASHINGTON, March 19 (Reuters) - Saudi Arabia called the 2015 nuclear deal between Iran and world powers a "flawed agreement" on Monday, on the eve of a meeting between the Saudi crown prince and U.S. President Donald Trump who have both been highly critical of Iran.
"Our view of the nuclear deal is that it's a flawed agreement," Saudi Foreign Minister Adel al-Jubeir told reporters in Washington.
The meeting between Crown Prince Mohammed bin Salman and Trump comes at a time when Riyadh and Washington have been strengthening their relationship after tensions under the previous U.S. administration, in part over Iran.
Jubeir called out Iran for what Riyadh has long slammed as Tehran's destabilizing behavior in the region. "We've called for tougher policies towards Iran for years," he said.
"We're looking at ways in which we can push back against Iran's nefarious activities in the region," Jubeir said, lambasting Tehran's support for the Houthi militia in Yemen and support for Syrian President Bashar al-Assad in Syria.
Iran denies interference in the region's affairs.
Saudi Arabia had viewed with unease the administration of U.S. President Barack Obama, which it felt considered Riyadhs alliance with Washington less important than negotiating the Iran nuclear deal.
Saudi state news agency SPA said the crown prince left for the United States on Monday to begin the visit, which is also expected to include meetings with business leaders and stops in New York, Boston, Los Angeles, San Francisco and Houston.
It is first visit by Mohammed bin Salman, or MbS as he known in Western circles, to the United States since he became heir apparent.
The ambitious young prince has embarked on reforms to modernize deeply conservative Saudi Arabia.
He visited Britain this month on his first foreign tour since his rise as part of efforts to persuade Western allies that "shock" reforms have made his country, the world's top oil exporter, a better place to invest and a more tolerant society.
He will meet Trump on Tuesday at the White House. He will also see members of the U.S. Congress, some of whom have been critical of the Saudi campaign in Yemen, particularly the humanitarian situation and civilian casualties.
Senior Trump administration officials who briefed reporters ahead of the visit said Trump wants to resolve a dispute between Gulf states and Qatar, although the Saudi foreign minister called the issue a "very small matter."
Trump also wants to arrange a summit of Gulf states, the officials said.
Commercial ties also figure into the visit.
"While the crown prince is in Washington, we will be advocating for $35 billion in commercial deals for U.S. companies that would support 120,000 American jobs," one official said.
Executives form the largest U.S. defense companies, including Lockheed Martin and Boeing plan to attend an industry round table with Prince Mohammed on Wednesday, people familiar with the plan said.
Top executives, including Lockheeds Marillyn Hewson and Boeings Dennis Muilenburg, plan on attending, the people said on condition of anonymity.
The prince also plans to meet with executives in the oil and gas industry in Houston, according to Jubeir. Without providing details, Jubeir said Riyadh would look to sign memorandums of understanding.
In addition, the crown prince will have meetings at Google and Apple, and meet with U.N. Secretary-General Antonio Guterres.
In his meetings with business, industry and entertainment leaders, the prince is aiming to cultivate investments and political support. Several dozen Saudi chief executives are expected to join him in touting investment opportunities in the kingdom.
Any visit to the New York Stock Exchange will be watched closely by investors because of the potentially lucrative listing of up to 5 percent of Saudi Aramco expected this year.
Sources close to the process said the kingdom is increasingly looking to just float the oil giant locally as plans for an initial public offering on an international exchange such as New York or London appear to be receding.
Saudi Energy Minister Khalid al-Falih said recently that Aramco was too important to risk listing in the United States because of litigation concerns, such as existing lawsuits against rival oil companies for their role in climate change.
Prince Mohammed has won Western plaudits for seeking to ease Saudi Arabia's reliance on oil, tackle chronic corruption and transform the Sunni Muslim kingdom.
But the severity and secrecy of an anti-corruption crackdown last November, after he was named heir to the throne, has unnerved some investors. (Additional reporting by Marwa Rashad in Riyadh and Steve Holland and Mike Stone in Washington Writing by Yara Bayoumy and Ghaida Ghantous Editing by Tom Brown and James Dalgleish)