World leaders are meeting with members of the Somali government to co-ordinate efforts against piracy, poverty and famine, and to discuss the country's civil war.
Forty countries are represented at Thursday's conference in London, and attendees include Hillary Clinton, the US secretary of state, and Ban Ki-moon, the UN secretary-general.
Other participants at the conference include representatives from the European Union, the African Union and the Arab League, as well as the head of the breakaway Somaliland region.
Opening the meeting, David Cameron, the British prime minister, said that Somalia's problems affected the entire world.
"If the rest of us just sit back and look on, we will pay a price for doing so. So as an international community, it is in all our interests to try and help the Somali people address these problems," he said.
Al-Shabab, a group of fighters who are fighting the Somali government, are not represented at the conference, and Abu Omar Abudurehman, an Al-Shabab commander, told Al Jazeera that if the conference results in "unwanted interference in Somalia" then it will lead to "an ugly turn of events".
Clinton said that Somalia was at a "critical" moment, and that international community must step in to support the establishment of a stable central government, beyond its current transitional authority.
She told the conference that her government will invest millions of dollars towards improving the situation in Somalia.
Gatherings similar to Thursday's meeting in the past 20 years have resulted in many foreign commitments of aid, but in little progress on the ground, sceptics say. Cameron referred to past engagement as "sporadic and half-hearted".
Britain, the country organising the conference, says the aim of the event is to galvanise policymakers' attention and to better co-ordinate a sometimes disjointed international response to Somalia's many challenges.
The conference will not be examining the clan-based politics which affect several aspects of Somali life and play a role in everything from business and piracy to the distribution of humanitarian aid.
Nevertheless, some analysts say that Somalis are expecting real progress to be made during the talks in London.
"The expectations that Somalis have are huge," Jabril Ibrahim Abdulle, a Mogadishu-based civic activist with the
Somalia Center for Research and Dialogue thinktank told Reuters.
"You have so many external actors driving different agendas that it would be a success to have a unified stance. Above all we need implementation of what's agreed, as disappointed hopes will only bring more radicalisation and hostility."
Abdiweli Mohamed Ali, the prime minister of Somalia's Transitional Federal Government (TFG), insisted on the eve of the conference that his country was "moving into an era of peace, stability and normalcy".
Al Jazeera's Nazanine Moshiri, reporting from Mogadishu, said: "The focus of the meeting will very much be on security issues, piracy, recent famine, but the crucial point of the conference is what is going to come next. After the end of the TFG's mandate in August.
"That is important because this country has not had a functioning government in decades, and without it there will be no progress here at all."
Clinton has said that the US will not back the extension of the TFG's mandate beyond August.
History of violence
Somalia collapsed into civil war between rival warlords, clans and factions after Siad Barre, the country's former military dictator, was overthrown in 1991. Up to a million people have been killed since then, according to the International Committee of the Red Cross (ICRC).
Currently, the weak Western-backed TFG, which controls only a limited area, is fighting a revolt by fighters belonging to the al-Shabab group. Al-Shabab recently announced that it was merging with al-Qaeda, and various countries' intelligence agencies say it harbours fighters who could be a threat to their nations.
Moses Wetangula, foreign minister of neighbouring Kenya, told Reuters he wanted to see "a renewed and reinvigorated
international commitment to Somalia".
"We hope it's not going to be the usual talking shop where we make flowery speeches and get clapped and go away without caring whether it will be followed up or not," he said.
Kenya deployed troops across the border with Somalia last year, aiming to target al-Shabab fighters, who were attacking Kenyan targets.
Somalia's TFG got a boost on the eve of the London conference when the UN Security Council voted to increase an African Union peacekeeping force by nearly half, seeking to press home gains made in a military offensive against al-Shabab.
The resolution increased the AMISOM force to 17,731 troops, from 12,000.
The UK Foreign Office said Thursday's meeting could build on "this good news, setting out a comprehensive international approach to Somalia covering politics, development, security, as well as our work to combat terrorism and piracy."
The military offensive against the rebels is ongoing, and on Wednesday, Ethiopian and Somali forces captured the al-Shabab stronghold of Baidoa in the south, the country's prime minister said.
The TFG's mandate ends in August, by which time it is to have enacted a new basic constitution and held an election.
Peter Pham, an expert on Somalia with the Atlantic Council, a US think-tank, said that similar conferences in the past had pretended that "Somalia is still a state when it has long ceased to be one".
"The only result this has produced is to incentivise the rent-seeking behaviour and corruption of so-called officials incapable of restoring a modicum of security and governance ... What is needed is a 'bottom-up' approach."
Al-Shabab, meanwhile, has rejected the conference.
"Somalia is a country blighted by all these years of foreign interventions and the London Conference would simply be another futile attempt to brush up the impotency surrounding the corrupt TFG," said Abudurehman.
"The London Conference is simply one of the many conferences held by the so-called international community, sort of to bring about an illusory stability to a country that's already under the governance of Islamic Sharia. And also an attempt ... to carve up Somalia and plunder its resources."