Update: Winners of the 2018 Nobel Peace Prize are Denis Mukwege and Nadia Murad
The Nobel Peace Prize will be announced in Oslo on Friday after a week of awards in honour of the philanthropist Alfred Nobel.
Prizes can be awarded to people or organisations, such as the nuclear disarmament group ICAN, which won last year. Previous winners have included Yasser Arafat, the Pakistani activist Malala Yousafzai and former US President Barack Obama.
Candidates can be nominated by heads of state, government ministers, senior academics and previous peace prize winners.
There are 331 candidates for this year's Nobel Peace Prize, 216 of which are individuals and the rest are institutions, but their names are kept secret.
Winners are chosen by a five-member panel selected from the Storting, Norway's parliament.
The Peace Prize is awarded in Oslo, not in Stockholm, Sweden, where Alfred Nobel was born and where the Nobel Prizes in Physics, Chemistry, Physiology or Medicine, Literature and the Economics Prize are being awarded this week.
Nominees for the Peace Prize are kept secret for 50 years. But Nobel-watchers and commentators on social media are fuelling speculation about possible candidates as the prize announcement approaches.
Here are some of the people and organisations being discussed:
Abiy Ahmed and Isaias Afwerki
Ending a 20-year conflict in a historic peace agreement, Ethiopian Prime Minister Abiy and Eritrean President Afwerki reopened links between their two countries. Families were reunited, border crossings opened and phone lines reconnected.
The peace deal, which was facilitated partly by the UAE, came just four months after Mr Abiy took office.
Surviving her kidnapping by ISIS in 2014, the Yazidi activist from Iraq campaigns for victims of human trafficking and refugees.
Ms Murad has worked with the United Nations, human rights lawyer Amal Clooney and Pope Francis on helping Yazidis who are still in captivity and highlighting the challenges religious minorities face in Iraq and Syria.
SOS Mediterranee and Doctors without Borders (MSF)
Co-operating the Aquarius, one of the few ships still rescuing migrants in the Mediterranean, SOS Mediterranee run the ship, while MSF provides medical assistance.
While the focus on the crisis has diminished, both organisations are advocating powerfully for migrant rights and highlighting the need for more assistance.
MSF also provides care for migrants after they arrive on European shores.
The Congolese gynaecologist founded the Panzi Hospital where he specialises in treating women who have been victims of gang rape.
Mr Mukwege is the world's leading expert in surgery following sexual assault and has treated thousands of women. He is in surgical theatre treating up to 10 people a day, often working 18-hour days.
In 2012 Mr Mukwege gave a speech to the UN and in 2014 he was awarded the European Union's highest human rights accolade, the Sakharov Prize for Freedom of Thought.
World Food Programme
The leading humanitarian organisation tackling food insecurity, the World Food Programme has helped feed those in unstable states.
In Syria and Yemen around 8 million people rely on WFP for food each month and in Myanmar, the WFT has helped feed displaced Rohingya Muslims.
The programme is also at the forefront of innovation on food sustainability, using blockchain technology, drones, mobile apps and self-driving vehicles to help feed the world.
South Korea's President had a historic summit with the North Korean dictator Kim Jong-un where peace between the two nations was declared. However, beyond promising signs through diplomacy and gestures of goodwill little of substance has been achieved.
Mr Smith said an award for Mr Moon would be "premature", recalling the dashed hopes after one of Mr Moon's predecessors, Kim Dae-jung, won the prize in 2000.
An unlikely runner, but not without precedent. His predecessor Barack Obama and three other US presidents have won the prize and Mr Trump's detente with Mr Kim has been hailed by his supporters as a prize-winning moment.
Dan Smith, head of the Stockholm International Peace Research Institute (SIPRI), told AFP he believed it would be "inappropriate" to honour Mr Trump after he withdrew the US from international agreements on climate and Iran's nuclear programme.
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