President Donald Trump has said the US has "no stronger partner" than Saudi Arabia during his first major foreign trip - a whirlwind visit of Gulf countries mainly focused on shoring up investment.

Speaking in Riyadh, the US president also pledged to lift all sanctions against Syria, saying it was now time for the country to move forward with "a chance at greatness".

Day one of the tour saw the US and Saudi Arabia announce a $142bn (£107bn) arms deal, as well as other investments that the country's crown prince said could eventually be worth $1tn.

Trump also made Saudi Arabia the first foreign stop during his first term, in 2017. The rest of his trip will include stops in Qatar and the UAE.

Trump's arrival in Saudi Arabia on Tuesday was met with a grand reception, including a lavish lavender-coloured carpet rolled out to greet him. He had even chosen a purple tie to match it.

Riyadh swapped red carpets for lavender in 2021, saying that it was a symbol of the kingdom's desert wildflowers and generosity.

Crown Prince Mohammed bin Salman met Trump on the tarmac and provided an honour guard of Arabian horses to accompany his presidential limo.

In his remarks at an investment forum, Trump lauded the US-Saudi relationship as "more powerful than ever before".

"From the moment we started, we've seen wealth that has poured - and is pouring - into America," he said.

Trump is trying to woo foreign investors to the US to boost the American economy, a key focus of his administration in the nearly four months of his second term.

"I like him too much," Trump said of Saudi Arabia's crown prince and de facto ruler, Mohammed bin Salman. "That's why we give so much."

The pomp and ceremony was a step up from the muted welcome for former US President Joe Biden, who travelled to the oil-rich kingdom in 2022 to seek their help in lowering petrol prices, fist-bumping the crown prince.

That visit came two years after he declared Saudi Arabia a "pariah" state following the 2018 murder of dissident journalist Jamal Khashoggi.

Trump flew to the Gulf to strike financial deals and argued in his speech that it is through this kind of commerce and economic development that the Middle East would transcend violence and division.

Underscoring his commitment to deal-making, Trump was joined by a number of business leaders, including billionaire ally Elon Musk, OpenAI CEO Sam Altman, BlackRock CEO Larry Fink and Nvidia CEO Jensen Huang.

The high-profile executives are meeting a Saudi Arabia eager to diversify its oil-rich economy by increasing its artificial intelligence capabilities.

Mr Huang announced during the visit that Nvidia will sell more than 18,000 of its latest AI chips to Saudi company Humain.

Chips from Blackwell, whose CEO was also present, will be used in data centres across Saudi Arabia, according to remarks made at the forum.

During his address, Trump said it was his "dream" to have Saudi Arabia join the Abraham Accords, a deal brokered in his first administration that saw relations between Israel and some Gulf countries normalised for the first time.

But his good friend, Mohammed bin Salman, has made it clear that will not happen until there is a permanent end to the war in Gaza and a clear path to Palestinian statehood.

There is a limit to what this friendship can deliver.

Trump only briefly addressed the ongoing conflict between Israel and Hamas.

He told those in attendance that people in Gaza deserved a "better future", which had been held back by Hamas choosing "to kidnap, torture and target" for "political ends" - a reference to the 7 October 2023 attack on Israel.

Trump also announced he was lifting sanctions on Syria to improve the country's new government, a move he suggested was requested by Mohammed bin Salman.

"Oh, what I do for the crown prince," the US leader said.

American sanctions on Syria had been in place for over a decade, meant to apply pressure and economic pain against the dictatorship of former President Bashar al-Assad, who was ousted in December.

Syria has since elected a new transitional president, creating an opening for renewed US diplomacy efforts.

The surprise announcement to lift the sanctions represents a sea change for Syria, described by its foreign minister Asaad Shibani as a "new start" in the country's reconstruction path.

Robert Ford, who served as US ambassador to Syria under the Barack Obama administration, applauded the Trump administration's move to lift sanctions.

"I visited Syria three months ago, and the country is simply devastated after the 13-year civil war. It needs to rebuild, it needs reconstruction, it needs foreign financing to do that," he told the BBC.

"So removing the sanctions, that will enable international capital flows to go into Syria from Gulf states, from other Arab states, and different aid agencies, is absolutely vital."

Trump was expected to meet Syrian President Ahmed al-Sharaa on Wednesday in Saudi Arabia.

From Riyadh, Trump will head to both Qatar and the UAE, which have already committed to investing $1.4tn in the US over the next decade.