The civil war in Syria contributed to push the numbers of refugees and those displaced by conflict within their own nation to an 18-year high of 45.2 million worldwide by the end of 2012, the UN refugee agency said Wednesday.

Those are the highest numbers since 1994, when people fled genocide in Rwanda and bloodshed in former Yugoslavia.

By the end of last year, the world had 15.4 million refugees, 937,000 asylum seekers and 28.8 million people who had been forced to flee within the borders of their own countries, the Office of the United Nations High Commissioner for Refugees said in a report.

Of those, 17 percent were new to their situations in 2012: 1.1 million new refugees and 6.5 million new internally displaced people.

That translates into someone becoming a new refugee or internally displaced person somewhere in the world every 4.1 seconds during the last year, said Antonio Guterres, head of the Geneva-based agency, also known as UNHCR.

"Which means each time you blink, another person is forced to flee," he told reporters in Geneva.

Children below the age of 18 accounted for 46 percent of refugees worldwide. Most of the refugees in the world have fled from five war-affected countries: Afghanistan, Somalia, Iraq, Syria and Sudan.

The overall numbers rose by 6 percent increase from the 42.5 million refugees and internally displaced people in the world at the end of 2011.