Nigerian President Goodluck Jonathan has ordered top security chiefs and officials to secure the safe release of 223 schoolgirls abducted three weeks ago by suspected Islamists.

Gunmen, believed to be Boko Haram Islamists, kidnapped the girls after storming their boarding school on 14 April.

Anger at the government's ineffectual response has fuelled protests at home and abroad.

Dozens of Nigerians staged a protest march in New York yesterday demanding action to free the children.

Mr Jonathan has now held closed-door talks with military and security service chiefs as well as senior officials, Borno state's governor and police chief, and the head of the school in Chibok where the girls were seized, spokesperson Reuben Abati told reporters.

Under pressure over the mass abduction, it was the first time the Nigerian leader brought together all key players involved in the search.

"The president has given very clear directives that everything must be done to ensure that these girls must be brought back to safety," Mr Abati said.

Until now the president had only conferred with his security chiefs.

Frustrated by the lack of progress, desperate parents yesterday called for Nigeria to seek foreign help to secure the girls' release.

"By all means, let's get the support we need from global players," said a former World Bank vice president, Obiageli Ezekwesili, in an interview in support of the distraught parents.

She was speaking at a sit-in by dozens of mothers in Abuja, who have vowed to keep up the pressure until their children are brought home.

Nigerian police on Friday said kidnappers were still holding 223 out of 276 girls seized from the school in the country's northeast.

Officials in Borno state had previously given lower figures on the number being held.

Boko Haram's name translates as "Western education is forbidden".

The group has repeatedly attacked schools during an insurgency aimed at creating a strict Islamic state in mainly Muslim northern Nigeria.

The Islamists have set schools on fire, massacred students in their sleep and detonated bombs at university campus churches, but a massive kidnapping specifically targeting girls is unprecedented.

The abduction is one of the most shocking attacks in Boko Haram's five-year uprising, which has left 1,500 people dead this year alone.