Soaring Disney shares lifted Wall Street to fresh records on Wednesday while stocks elsewhere in the world sagged as new signs emerged that Washington and Beijing are not as close to signing a trade deal as investors had hoped.

Asian trading suffered also from violent Hong Kong protests that showed no sign of letting up, while US investors evaluated testimony by Federal Reserve Chairman Jerome Powell before Congress.

The Fed chief told US lawmakers the economy would probably continue to grow but faced risks from a global slowdown and trade disputes.

In Washington, lawmakers also opened the first day of televised impeachment hearings during which the top US diplomat in Ukraine leveled fresh accusations about President Donald Trump's conduct that country.

The Walt Disney Co shot more than seven percent higher, its biggest one-day gain since April, after reporting that its streaming service Disney+ had attracted 10 million subscribers on its first day.

This helped lift the benchmark Dow Jones Industrial Average and S&P 500 to fresh records -- though New York stocks pared gains in mid-afternoon following a new report by The Wall Street Journal saying Chinese officials hesitated to agree formally to making gigantic purchases of American farm exports.

Trump last month announced a "phase one" deal had been agreed but efforts to commit the deal to paper appear to have hit roadblocks.

In a briefing Wednesday after markets closed, Trump said "our trade agreement with China is moving along very rapidly."

Hong Kong investors are  bracing for fresh unrest after the city saw another night of chaos
Hong Kong investors are bracing for fresh unrest after the city saw another night of chaos AFP / DALE DE LA REY

But Rufus Yerxa, president of the National Foreign Trade Council, told AFP on Wednesday the reported disagreements -- over whether and when to roll back tariffs and what volume of US farm exports China will buy -- were grounds for concern.

"It certainly suggests that we're not as a close to a deal as had been represented," he said.

In the first of back-to-back days of testimony before Congress, meanwhile, Powell reaffirmed that the US central bank is on hold after cutting the benchmark lending rate three times this year.

"He did not deliver anything new but he delivered his message clearly: no need for more easing but they would ease if they needed to," Karl Haeling of LBBW told AFP.

In Europe, the London stock market index closed with a small loss of almost 0.2 percent, Paris also gave up around 0.2 percent and Frankfurt was down by 0.4 percent.

Underscoring global gloom was concern about unrest in Hong Kong, which had suffered a night of rage as months of protests enter a more violent phase.

Police warned the rule of law there was on "the brink of total collapse."

Hong Kong's Hang Seng Index plunged by 1.8 percent, having shed a similar amount on Monday before staging a small rebound on Tuesday.

A bundle that offers video streaming users everything that they want at a price cheaper than a Netflix subscription. AFP/Robyn Beck

New York - Dow: UP 0.3 percent at 27,783.59 (close)

New York - S&P 500: UP 0.1 percent at 3,094.04 (close)

New York - Nasdaq: DOWN 0.1 percent at 8,482.10 (close)

London - FTSE 100: DOWN 0.2 percent at 7,351.21 points (close)

Frankfurt - DAX 30: DOWN 0.4 percent at 13,230.07 (close)

Paris - CAC 40: DOWN 0.2 percent at 5,907.09 (close)

EURO STOXX 50: DOWN 0.3 percent at 3,699.50 (close)

Tokyo - Nikkei 225: DOWN 0.9 percent at 23,319.87 (close)

Hong Kong - Hang Seng: DOWN 1.8 percent at 26,571.46 (close)

Shanghai - Composite: DOWN 0.3 percent at 2,905.24 (close)

Pound/dollar: UP at $1.2849 from $1.2845 at 2100 GMT

Euro/pound: DOWN at 85.64 from 85.70 pence

Euro/dollar: DOWN at $1.1004 from $1.1009

Dollar/yen: DOWN at 108.84 yen from 109.01 yen

Brent North Sea crude: UP 0.5 percent at $62.37 per barrel

West Texas Intermediate: UP 0.6 percent at $57.12