SINGAPORE (Reuters) -Global shares slipped on Wednesday and gold pulled back sharply from a blistering rally, as stretched valuations came under scrutiny and investors booked profits.

Geopolitics loomed large. A planned summit between U.S. President Donald Trump and Russian President Vladimir Putin was put on hold and ambiguity lingered over a potential meeting between Trump and Chinese President Xi Jinping.

Despite Washington and Beijing striking a more conciliatory tone in recent times, Trump added to the uncertainty over the meeting on Tuesday, saying that "maybe it won't happen".

The overnight dive in gold was the main focus for markets, after prices of the yellow metal sank more than 5% on Tuesday despite no obvious catalyst. It last traded 0.6% lower at $4,098.89 an ounce. [GOL/]

The precious metal has had a blockbuster run this year, climbing more than 50% as broader geopolitical and economic uncertainty, as well as expectations of U.S. interest rate cuts, spurred demand for the safe-haven asset.

"Gold was massively stretched, massively overbought. There's been a lot of FOMO (fear of missing out) going into that market," said Tony Sycamore, a market analyst at IG.

"It's one of those situations whereby when positions become stretched - and you'd have to say that the Nasdaq is certainly in that boat as well, for some of these other frothy markets, we're seeing little flash crashes now...We're just seeing little tremors in markets, and potentially there's something more significant to come."

MSCI's broadest index of Asia-Pacific shares outside Japan was down 0.24%, while Nasdaq futures fell 0.2% and S&P 500 futures dipped 0.07% after a mixed cash session on Wall Street.

Shares of Netflix sank nearly 6% after the bell as the streaming giant missed Wall Street's third-quarter earnings targets, while General Motors' stock surged 15% after the company raised its profit outlook for the year.

Elsewhere, EUROSTOXX 50 futures fell 0.5%, while FTSE futures eased 0.15% and DAX futures lost 0.26%.

Japan's Nikkei fell 0.9%, in line with the broader market, though that followed two days of strong gains on expectations of greater fiscal stimulus under the country's new prime minister Sanae Takaichi.

"We expect 'Sanaenomics' to be broadly positive for the equities market," said Louis Chua, a research analyst at Julius Baer.

He expects further upside for the Nikkei, supported by the "twin tailwinds of corporate reform and a pro-growth reflationary path with Takaichi's election".

In China, the CSI300 blue-chip index fell 0.2%. Hong Kong's Hang Seng Index slipped 0.42%.

WAITING ON CENTRAL BANK CUES

In currencies, the yen was nursing losses after sliding nearly 0.8% in the previous session on the back of Takaichi's win, which investors expect could muddy the outlook for the Bank of Japan's (BOJ) rate-hike path.

The BOJ meets next week, where expectations are for the central bank to stand pat on rates.

"The likelihood of a rate hike in October has remained low for some time," said analysts at Morgan Stanley MUFG Securities in a note.

"Whether there will be a subtle positive change in Governor (Kazuo) Ueda's comments during the press conference, namely in his evaluation of tariff impacts on the U.S. economy and their effects on Japanese companies, will likely become an important point in assessing the possibility of a rate hike at the next December meeting."

The U.S. Federal Reserve also announces its rate decision next week, and investors have almost fully priced in a 25-basis-point rate cut.

The dearth of U.S. economic data due to the ongoing government shutdown means that policymakers could be left flying blind at the meeting, a less-than-ideal situation as they remain divided over which risks deserve the most attention.

Trump on Tuesday rebuffed a request by top Democratic lawmakers to meet until the three-week-old U.S. government shutdown ends.

The shutdown has in turn left currencies largely rangebound over the past few sessions due to the lack of fresh catalysts from data releases, though the dollar was largely steady on Wednesday, helped by a weaker yen.

The euro last bought $1.1604, while sterling dipped slightly to $1.3370.

In commodities, oil prices edged higher, with Brent crude futures up 0.31% at $61.51 a barrel, while U.S. crude rose 0.38% to $57.46 per barrel. [O/R]