The world comes to London

US

Who's coming?

President Barack Obama and wife Michelle with delegation including Treasury Secretary Timothy Geithner, Secretary of State Hillary Clinton. Staying at US ambassador's residence, Winfield House.

What does he want?

Co-ordinated response to crisis, stimulus package, new regulatory structures. Series of bilateral meetings, plus visiting the Queen at Buckingham Palace before the other G20 leaders meet her.

Distinguishing feature

Walks on water but may not show off skill.

China

Who's coming?

President Hu Jintao and delegation including officials from Hong Kong. Working groups have been in London since beginning of March

What does he want?

Alternative to dollar as global reserve currency, but this proposal unlikely to be taken up. IMF voting rights. Also holding his first summit with President Obama, which is expected to focus on global warming.

Distinguishing feature

Will not be seen with President Nicolas Sarkozy who has upset the Chinese over Tibet.

Japan

Who's coming?

Prime Minister Taro Aso travelling with his finance minister, veteran politician Kaoru Yosano, and the foreign minister.

What does he want?

An economic stimulus package is a priority as world's second largest economy is poised to descend into deflation again. Mr Aso places importance on reviving the world economy, but also wants reforms to regulation and the IMF.

Distinguishing feature

Looking smug, as he was the first foreign leader to be invited to the White House by President Obama.

India

Who's coming?

The Prime Minister, Manmohan Singh, will be flying in to London on Tuesday accompanied by the acting Finance Minister and delegation.

What do they want?

To avoid awkward questions about protectionism, which has put India in Obama's firing line. The US is keen to boost trade with India, but Singh is cautious about possible impact domestically. He has bagged a meeting in London with Obama.

Distinguishing feature

Knows issues inside out as UK-educated economist turned politician.

Germany

Who's coming?

The delegation will be led by Chancellor Angela Merkel. Likely to be a flying visit because she is hosting Nato's 60th birthday celebrations in Kehl next weekend.

What does she want?

Tougher financial regulation and reform of the International Monetary Fund. Opposed to any mass stimulus of the global economy.

Distinguishing feature

The most senior female participant in the talks. Will be dreading Gordon Brown's notoriously awkward bear-hug embrace.

UK

Who's coming?

Gordon Brown, supported by Chancellor Alistair Darling, Foreign Office minister Mark Malloch-Brown and Trade minister Shriti Vadera. Also Jon Cunliffe, the Cabinet Office head of international economic affairs and Europe.

What does he want?

Ideally, a fiscal boost to the world economy, tougher bank regulation, extra money for the IMF and crackdown on tax havens. But being forced to lower his sights.

Distinguishing feature

Summit host at "make or break" moment.

Russia

Who's coming?

President Dmitry Medvedev and a large delegation of advisers, economic experts and press team.

What does he want?

Improved international regulation and IMF reform. But main event will be his summit next Wednesday with President Obama focusing on proposed nuclear weapons cuts.

Distinguishing feature

Will not be accompanied by his minder, Vladimir Putin, on his first major outing on the world stage. Maybe listening to Deep Purple on his iPod (pronounced eepod in Russian).

France

Who's coming?

President Nicolas Sarkozy, sadly without wife Carla, but with Finance Minister Christine Lagarde and Foreign Minister Bernard Kouchner. Delegation staying at Sofitel hotel.

What does he want?

Tighter financial regulations particularly over hedge funds, with sanctions. More funds for international financial bodies. Opposed to more spending to boost economies.

Distinguishing feature

Napoleon complex. Will push to the front as he doesn't like being upstaged.

Brazil

Who's coming?

President Luis Inacio Lula da Silva with his finance and foreign ministers and a delegation of 20.

What does he want?

To make the "white, blue-eyed" people in rich countries he blames for creating the global economic crisis pay for their mistakes. Opposed to protectionism.

Leading the developing nations in calling for bigger role after reform of the IMF

Distinguishing feature

Populist president may spring a surprise on the summit promising it will be "a bit spicy".

Italy

Who's coming?

Prime Minister Silvio Berlusconi, who sees himself as dean of Western leaders, aged 72.

What does he want?

No protectionism, but co-ordinated market regulation. As host of G8 in July, he is trying to change its image from a club for rich nations, pushing for a "global welfare pact" before 2 April. Plans to host G20 leaders at the end of G8 summit in Sardinia.

Distinguishing feature

Gaffe-prone prime minister likely to offer good value again by insulting fellow leaders.

Mexico

Who's coming?

President Felipe Calderon and his wife Margarita Zavala accompanied by delegation.

What does he want?

Co-ordinated global action to stimulate the economy and IMF reform. Presmably not happy being consigned to second tier of states (along with Russia) by UK government.

Distinguishing feature

Faint air of superiority having enjoyed a state visit beforehand, including lunch with the Queen, and a visit with the Duke of York to Aberdeen.

Canada

Who's coming?

Prime Minister Stephen Harper and his Finance Minister, Jim Flaherty, with delegation.

What does he want?

To fix the banks in order to restore lending, and a rapid delivery of economic stimulus package pledged by G20 last November. No protectionism. Greater transparency to restore confidence in global financial system.

Distinguishing feature

Politically astute, Harper will go with the flow. Former Bush-loving PM now loves Obama following presidential visit to Canada.

South Korea

Who's coming?

President Lee Myung-bak flying to London with planeload of officials and advisers, including finance, trade and foreign ministers.

What does he want?

Seoul has already introduced its own stimulus package including tax cuts and wants global co-ordination. Opposed to protectionism. Has scheduled talks with Obama in London.

Distinguishing feature

Lee, nicknamed "The Bulldozer", is a former CEO of Hyundai and a force to be reckoned with.

Turkey

Who's coming?

Prime Minister Recep Tayyip Erdogan, his wife Emine, and delegation. Staying at Hilton Park Lane and Dorchester.

What do they want?

Western economic stimulus: Turkey's manufacturing industry has been hit by the downturn. Otherwise he's pretty satisfied: President Obama heads to Turkey for a summit three days after G20.

Distinguishing feature

Ear glued to his mobile phone for news from home, with local elections scheduled three days later. His wife is the one in the headscarf.

Indonesia

Who's coming?

President, Susilo Bambang Yudhoyono will be leading the Indonesian delegation.

What does he want?

Major reforms to the world's global financial institutions, including the World Bank and the IMF, to speed up payments to developing countries. He is critical of financial bodies for forcing developing nations to liberalise their markets in exchange for aid.

Distinguishing feature

Don't mess with this decorated former army general who is a feisty spokesman for developing nations.

Australia

Who's coming?

Prime Minister Kevin Rudd accompanied by his wife Therese Rein and delegation, having flown in from meeting in Washington with President Obama.

What do they want?

Agrees with need for continued stimulus and globally co-ordinated solution to toxic bank assets. Opposed to protectionism. In favour of IMF reform, and ongoing G20 process with another summit this year, ideally in Asia.

Distinguishing feature

Cool exterior belies inner chaos. May wear RM Williams boots.

Saudi Arabia

Who's coming?

King Abdullah bin Abdul Aziz Al Saud, accompanied by a retinue of advisers and possibly four wives which would complicate Sarah Brown's wives' summit.

What does he want?

As the only Opec representative, will highlight energy security. IMF reform, but would resist shouldering too much of the burden of a cash injection.

Distinguishing feature

The most powerful leader in the G20 roll- call. Also the easiest to recognise thanks to his headgear.

Argentina

Who's coming?

Cristina Fernandez de Kirchner expected to be accompanied by her husband, Nestor, whom she succeeded as president.

What does she want?

Will argue against any return to protectionism and will be keen to raise her nation's profile. Will also be sceptical about the wisdom of stimulus packages. Wants a greater voice for developing countries within the IMF.

Distinguishing feature

She will feel a sense of history – the 2 April summit takes place on the 27th anniversary of the Falklands invasion.

South Africa

Who's coming?

President Kgalema Motlanthe will attend along with three key government ministers. But will the President be accompanied by his long-term lover Gugu Mtshali?

What does he want?

Steadier flows of credit to help keep his country's economy afloat, as well as a bigger role for developing nations in running the IMF.

Distinguishing feature

Could be preoccupied by concerns back home – South Africa holds a general election on 22 April which will seal the fate of the caretaker President.

EU

Who's coming?

Outgoing Czech Prime Minister Mirek Topolanek representing the EU presidency despite being voted out of office. But EU Commission president Jose Manuel Barroso also in attendance.

What do they want?

Mr Topolanek will be speaking on behalf of the agreed EU position which backs fiscal stimulus and other financial measures, despite dismissing Obama's stimulus plan as the "road to hell".

Distinguishing feature

The only man enjoying the summit knowing he won't be around later.