World News Update, what you need to know

Israel has sharpened its campaign against Gaza, warning Palestinians in the north to flee after marines mounted a ground attack, as diplomatic efforts to halt the bloodshed intensified.

ELSEWHERE:

KIEV - Escalating clashes between pro-Kremlin separatists and Ukrainian forces have killed 18 civilians and forced the new Western-backed leader to cancel a pivotal meeting with Russian President Vladimir Putin at the World Cup in Brazil.

VIENNA - Western foreign ministers appeared to have failed in their mission to inject momentum into talks with Iran, seven days before the deadline to strike a momentous nuclear deal.

PARIS - Greenhouse gases and depletion of the ozone layer are causing southern Australia to become drier, researchers say.

VIENNA - Germany and the United States remain "great friends" despite a new spying scandal that saw the CIA station chief in Berlin expelled, US Secretary of State John Kerry says.

TRIPOLI - Deadly clashes raged around Libya's main international airport, closing it down, as the anti-Islamist militia that control it came under attack, airport officials say.

CASABLANCA - The death toll after three buildings collapsed in Morocco's largest city and commercial capital Casablanca has risen to 13.