A teenaged boy opened fire with a handgun at a Kentucky high school on Tuesday morning, leaving two fellow students dead and more than a dozen people wounded in the latest mass shooting to hit the United States.

After a gala opening set against spectacular snowfall, the World Economic Forum starts in earnest on Tuesday basking in robust global growth but facing warnings that the world's have-nots are missing out more than ever.

The global unemployment rate is expected to tick down in 2018, the United Nations said Monday, while warning that far too many workers still live in desperate poverty.

A rare heavy blanket of snow in Tokyo on Tuesday left thousands of travellers stranded and scores injured, as frozen conditions snarled public transport in the Japanese capital.

Former defence secretary Michael Fallon joined calls Monday for more British military spending, as the head of the army said the country may struggle to match Russian battlefield capabilities and another security chief warned a major cyber-attack on the UK is likely by 2020.

Britain would struggle to match Russian military capabilities on the battlefield and risks falling further behind potential adversaries without more investment, the head of the army will warn Monday.

Syria's main opposition group said it will send a delegation Monday to regime ally Russia to discuss with officials Moscow's "real stance" on the Syrian political process.

Two prison guards were hospitalised on Sunday after being assaulted with a table leg by an inmate at a jail in northern France, the latest in a spate of prison attacks that has led to nationwide strike action.

Gunmen stormed a luxury hotel in Kabul and killed at least 18 people, most of them foreigners, sparking a 12-hour battle with Afghan forces backed by Norwegian troops that left terrified guests scrambling to escape.