The U.N. humanitarian chief says Cameroon is facing worsening violence and conflict and the number of people needing humanitarian assistance has increased 30 percent from last year to 4.3 million people.

Mark Lowcock told an informal Security Council meeting Monday that this means one in six Cameroonians need aid — more than half of them children.

He said the biggest challenge is lack of funding.

English-speaking separatists in the Northwest and Southwest regions allege years of marginalization by the government of largely French-speaking Cameroon. Hundreds have been killed as fighters from a number of armed groups battle government forces and attempt to economically paralyze the regions.

The United States organized the informal meeting over objections from the council's three African members and strong opposition from the Cameroonian government.