(Reuters) -Prime Minister Benjamin Netanyahu said on Thursday that Israel will begin immediate negotiations for the release of all hostages held in Gaza and an end to the nearly two-year-old war on terms acceptable to Israel.

Speaking to soldiers serving in Gaza, Netanyahu said he was meeting commanders to approve plans for capturing Gaza City and defeating Hamas.

Severely malnourished children in the Gaza Strip will be "certainly condemned to death" unless aid gets to them quickly, UNRWA chief Philippe Lazzarini warned Thursday.

The head of the UN agency for Palestinian refugees said hunger was particularly acute in the north -- where Gaza City is -- where an estimated one million people remain.

Lazzarini said an evaluation on how famine has evolved in the Gaza Strip was due to be published soon, adding UNRWA health centres had seen a six-fold increase in the number of severely malnourished children since March.

LONDON (Reuters) -Britain summoned Israel's ambassador in London on Thursday following Israel's approval of a widely condemned settlement plan that would cut across land which the Palestinians seek for a state.

Britain, along with other European nations, has slammed the plan as a "flagrant" breach of international law that would undermine the idea of a two-state solution.

(Reporting by Sachin Ravikumar; editing by Michael Holden)

BEIRUT (Reuters) -Lebanon said on Thursday it was launching the planned disarmament of Palestinian factions in refugee camps, part of a wider effort to establish a state monopoly on arms.

The planned disarmament was starting with the handover of weapons on Thursday from the Burj al-Barajneh camp in Beirut to the Lebanese army, the Lebanese prime minister's office said.

Some armed Palestinian groups in Lebanese refugee camps began handing over their weapons to the authorities on Thursday after reaching a deal earlier this year, with Washington hailing the move as a "historic step".

The efforts at disarmament came after the Lebanese government, under US pressure, tasked the army with formulating a plan to also disarm the militant group Hezbollah by the end of the year.

The Lebanese army took into its custody a number of weapons in the Burj al-Barajneh refugee camp in Beirut's southern suburbs.

By Nailia Bagirova

BAKU (Reuters) -Rapid falls in the level of the Caspian Sea are affecting ports and oil shipments and threatening to inflict catastrophic damage on sturgeon and seal populations, according to Azerbaijani officials.

The Caspian, the world's largest salt lake, holds significant offshore oil reserves and is bordered by five countries that are all major producers of oil or gas or both: Azerbaijan, Iran, Kazakhstan, Russia and Turkmenistan.

DUBAI (Reuters) -Iran on Thursday launched its first solo military exercises since its June war with Israel, state media reported, seeking to reassert an image of strength after suffering heavy losses.

Navy units of Iran's regular armed forces fired missiles and drones at open water targets in the Indian Ocean under the "Sustainable Power 1404" drill, state television reported.

GENEVA (Reuters) -The head of the U.N. Palestinian refugee agency on Thursday voiced concern that children suffering from malnutrition in Gaza would die if emergency provisions are not immediately put in place during Israel's Gaza City military operation.

UNRWA Commissioner-General Philippe Lazzarini said that its data showed a six-fold increase in the number of children suffering from malnutrition in Gaza City since March.

ANKARA (Reuters) -Turkey believes a ceasefire must first be secured between Russia and Ukraine before it and other states take any decisions on a peacekeeping mission as part of security guarantees for Ukraine, a defence ministry source said on Thursday.

U.S. and European military planners have begun exploring security guarantees for Ukraine, Reuters reported on Tuesday, a day after President Donald Trump said the U.S. would help guarantee its security in any deal to end the war.

By Nidal al-Mughrabi and Lili Bayer

CAIRO/JERUSALEM (Reuters) -The Israeli military maintained its pressure on Gaza City with heavy bombardments overnight, residents said, ahead of a Thursday meeting between Prime Minister Benjamin Netanyahu and his ministers on plans to seize the enclave's largest city.