Sultan of Oman ends two-day state visit to Belgium
Gulf leader was invited to Brussels as both countries look to boost co-operation in security and clean energy
What the Gulf's population boom means for illegal migration
Rapid growth is fuelling the need for more labour – and with it the pressure to root out bad actors in the system
Much talk but little action on climate refugee crisis, says UNHCR official
Refugee camps are often the most vulnerable to extreme weather
