LONDON: Global stock markets remained cautious on Tuesday, with investors spooked by Russia's deadly subway explosion and a looming US-China summit, dealers said.

The Saint Petersburg metro attack Monday, which left 14 dead and dozens injured, sent investors rushing for haven investments like gold and the yen.

Sentiment has also been hampered so far by growing anxiety over this week's crucial US-China summit.

In Asia, Tokyo led the fallers on Tuesday, hit by a stronger yen that punishes shares in Japanese exporters. Hong Kong and Shanghai were shut for holidays.

But stocks prices in Frankfurt, Paris and London shrugged off that weakness to remain steady or edge higher in mid-afternoon trade.

Stock markets were "vulnerable to downside shocks ... as investors lost appetite for risk ahead of the Trump-Xi summit this week," said FXTM analyst Lukman Otunuga.

"Wall Street may be in store for further punishment moving forward as risk-off is the name of the game ahead of the meeting between Donald Trump and Chinese President Xi Jinping," the expert continued.

"While the fanatical optimism over Trump's proposed fiscal policies boosting US growth has fuelled the phenomenal stock market rally, the rising protectionist fears and concealed concerns over the pro-growth agenda falling short of expectations could catalyse an unexpected selloff," he warned.

On Thursday and Friday, Trump will host Xi at his Mar-a-Lago resort in Florida. The encounter is expected to address disputes over trade policy between the world's two most powerful nations and leading economies.

Trump recently said he expects the meeting with Xi "will be a very difficult one." It follows a series of attacks by him on Beijing's trade policies and accusations it is a currency manipulator.

Back in Moscow, Russia's Investigative Committee said Tuesday that they suspected a suicide bomber was behind the attack in the Saint Petersburg metro.

The death toll from the bombing in Russia's second city rose to 14 on Tuesday, as Kyrgyzstan said a suicide bomber from the Central Asian country had staged the attack.

Investors will also focus this week on the March US jobs report and the release of minutes from the most recent monetary policy meetings of the US Federal Reserve and European Central Bank.

In London on Tuesday, gold prices advanced to $1,256.90 per ounce from $1,247.50 late on Monday. -- AFP