A rally on hopes for progress in the US-China trade war fizzled late Friday, sending Wall Street into the red after bourses elsewhere had drifted higher earlier in the day.

A delegation of Chinese officials on Friday abruptly canceled hastily-scheduled visits to farms Nebraska and Montana.

While mid-level trade talks continued uninterrupted in Washington, the visits' sudden cancelation spooked investors on Wall Street, sending all three major indices in the red.

US stocks fell for the week after three straight weeks of gains.

Earlier in the day, reports that President Donald Trump was exempting hundreds of Chinese imports from tariffs imposed last year had lifted spirits in Frankfurt, Paris and Shanghai.

The results capped a tumultuous week during which attacks on Saudi oil facilities sent oil prices skyrocketing, and investors reacted ambivalently to a widely-anticipated interest rate cut by the US central bank.

Central bankers also took emergency action for the first time in a decade to pump cash into the US money market to prevent the Fed from losing control of interest rates.

"An awful lot to absorb this week for the market," Quincy Krosby of Prudential Financial told AFP.

The Chinese officials' early departure raised eyebrows among investors especially after Trump's remarks on Friday seemed to dampen plans for an early trade pact.

"The president came out with comments he does not want a trade deal before the election. That said, they are still going to the high level meeting in October," Krosby said.

"But we are again on the on-off relationship between the US and China."

CMC Markets UK analyst David Madden, said, "Neither side wants to be seen as very eager to reach a deal but the fact that talks took place is a positive step."

The pound was mixed despite even though Britain claimed momentum in talks on a Brexit deal and European Commission chief Jean-Claude Juncker's appeared to hint that one was still possible, before the deadline at the end of October.

Nevertheless sterling it was solidly higher compared with a week ago, which did not help shares of international companies listed on the London Stock Exchange. The blue-chip FTSE 100 index fell.

London sentiment was buoyed Friday after Royal Bank of Scotland appointed long-serving banker Alison Rose as chief executive, making her the first female boss of a major UK lender.

The news sent RBS shares jumping 2.6 percent higher to stand at 213.5 pence.

Both main contracts for crude oil then stabilized this week after the initial shock but there are worries of a possible conflict after the United States and Saudi Arabia pointed the finger at Iran and said they were considering their response.

Iran's Foreign Minister Mohammad Javad Zarif warned Thursday that any military strike on the country could lead to "all-out war."

Key figures around 2100 GMT

New York - Dow: DOWN 0.6 percent at 26,935.07 (close)

New York - S&P 500: DOWN 0.5 percent at 2,992.07 (close)

New York - Nasdaq: down 0.8 percent at 8,117.67 (close)

London - FTSE 100: DOWN 0.3 percent at 7,337.11 points (close)

Frankfurt - DAX 30: UP less than 0.1 percent at 12,468.01 (close)

Paris - CAC 40: UP 0.6 percent at 5,690.78 (close)

EURO STOXX 50: UP 0.5 percent at 3,571.39 (close)

Tokyo - Nikkei 225: UP 0.2 percent at 22,079.09 (close)

Hong Kong - Hang Seng: DOWN 0.1 percent at 26,435.67 (close)

Shanghai - Composite: UP 0.2 percent at 3,006.45 (close)

Euro/dollar: DOWN at $1.1021 from $1.1041 at 2100 GMT

Dollar/yen: DOWN at 107.56 yen from 108.02 yen

Pound/dollar: DOWN at $1.2476 from $1.2526

Euro/pound: UP at 88.33 pence from 88.15 pence

Brent North Sea crude: DOWN 0.2 percent at $64.28 per barrel

West Texas Intermediate: DOWN 0.1 percent at $58.09