MAIDUGURI, Nigeria, Jan 20 (Reuters) - Islamist militants attacked a facility housing several aid groups in northeast Nigeria at the weekend in what the United Nations warned on Monday is an escalation in violence specifically targeting aid workers.

BRUSSELS, Jan 20 (Reuters) - European Union foreign ministers agreed on Monday to look at ways to support a formal ceasefire in Libya if warring sides can move beyond a tentative truce, including a monitoring mission and reviving a naval operation to uphold a U.N. arms embargo.

DUBLIN (Reuters) - Owners of Boeing's grounded 737 MAX jet must keep cool heads and avoid offering panic discounts on sale or lease prices to avoid undermining its long-term value, the head of one of the world's largest aircraft lessors Aercap said on Monday.

LONDON (Reuters) - Britain's Prince Harry has spoken of his sadness at being forced to give up his royal duties in a deal with Queen Elizabeth and senior Windsors, saying there was no other option if he and his wife Meghan were to seek an independent future.

DUBLIN (Reuters) - The chairman of major aircraft leasing firm Air Lease , which has 150 of Boeing's grounded 737 MAX jet on order, on Monday called on the U.S. manufacturer to drop the "damaged" MAX brand to avoid it undermining the plane's value.

LONDON (Reuters) - Oil prices rose to their highest in more than week on Monday after two large crude production bases in Libya began shutting down amid a military blockade, risking reducing crude flows from the OPEC member to a trickle.

BERLIN, Jan 20 (Reuters) - Libya will face a "catastrophic situation" unless foreign powers put pressure on eastern-based commander Khalifa Haftar to lift a blockade of oilfields that has cut output to almost zero, the country's internationally recognized premier said on Monday.

BASEL/LONDON (Reuters) - Central banks can't be expected to save the world from climate change, a new book by the Bank for International Settlement said on Monday, urging instead global co-ordination ranging from government policy to financial regulation.

BASEL/LONDON, Jan 20 (Reuters) - Central banks can't be expected to save the world from climate change, a new book by the Bank for International Settlement said on Monday, urging instead global co-ordination ranging from government policy to financial regulation.