TIMELINE: From summit to summit - G20 to meet in Pittsburgh

(Reuters) - World leaders are due to meet September 24-25 in the U.S. city of Pittsburgh for their third summit in less than a year to discuss their response to the global financial crisis.

Below is a summary of meetings involving leaders and ministers from the Group of 20 industrialized and developing countries since the first G20 leaders summit in November 2008.

November 15, 2008:

Group of 20 leaders from rich and emerging market nations meet in Washington and agree an "action plan" to try to restore global growth and bring order to a financial system reeling from a worldwide credit crisis.

The G20 leaders pledge to "work together to restore global growth" but stop short of any coordinated new fiscal measures.

February 14, 2009:

G7 powers end crisis talks in Rome with a pledge to do all they can to combat recession without distorting free trade.

Statement says that stabilizing the economy and financial markets is paramount, meaning that all had to work together and use all possible policy options to maximum effect.

Germany and Britain start the meeting with warnings that the world must avoid repeating the protectionist spiral that played a role in deepening the 1930s Great Depression.

February 22, 2009:

German Chancellor Angela Merkel invites fellow EU leaders to a one-day summit in Berlin. European leaders agree at the summit to push for a global crackdown on tax havens and strict new regulation of hedge funds.

March 1, 2009:

Special meeting in Brussels of EU leaders to discuss efforts to stabilize the financial sector.

March 13/14, 2009:

Finance ministers, at a preparatory meeting for the G20 leaders summit in Sussex, promise rescue money for troubled emerging market economies.

March 19/20, 2009:

At a summit in Belgium, the EU pledges more than $100 billion in new loans to the IMF to bail out countries hit by the global recession and urges the G20 to help double its funding.

EU leaders also agree to double to 50 billion euros ($68.5 billion) a crisis fund which can be used by struggling member states which do not use the euro.

April 2, 2009:

G20 leaders meet in London and agree to commit new resources of 1.1 trillion dollars that are available to the world economy through the IMF and other institutions.

This includes 250 billion dollars of IMF reserve units called Special Drawing Rights. In addition, the IMF would see its own resources tripled, with up to $500 billion of new funds.

The G20 also agreed a trade finance package worth $250 billion over two years to support global trade flows.

The summit also signed off on plans to commission blacklists of tax havens and tighten financial rules to bring hedge funds and credit rating agencies under closer supervision.

April 18/20, 2009:

G8 farm ministers as well as ministers from Brazil, China, India, Mexico, South Africa, Argentina, Australia and Egypt, takes place in Italy and urges that more food be grown to feed the world's hungry. They also say that investment in sustainable farming and rural development needed to be increased.

April 24-26, 2009:

G7 finance ministers and central bankers meet in Washington. Ministers from the IMF and World Bank warn that the crisis risks derailing universally agreed U.N. targets to overcome poverty by 2015.

June 12/13, 2009:

Finance ministers from the G8 nations, meeting in Lecce in southern Italy, describe their economies in the most positive terms since the crisis erupted. They started considering how to roll back the steps taken to fight the crisis once the economic recovery becomes certain.

The U.S. and others, however, warn there must be firmer signs of recovery before any of the massive public stimulus for the economy is withdrawn.

July 8-10, 2009:

Leaders of G8 nations meet for annual summit at L'Aquila, scene of April's earthquake.

The G8 acknowledges there are still risks to financial stability from the economic crisis, but tough new rules for global finance will be left to a September G20 meeting.

Talks on global warming produce chequered results, making only limited progress following the refusal by major developing nations to sign up to the goal of halving world greenhouse gas emissions by 2050. Major economies did agree to restrict global warming to 2 degrees Celsius (3.6 Fahrenheit).

The G8, G5, South Korea, Egypt, Australia agree to complete the long-stalled Doha trade talks in 2010.

G8 AND BEYOND:

September 5, 2009:

G20 finance leaders take aim at excessive bank pay and risk-taking at the root of the financial crisis and insisted trillions of dollars of emergency economic supports would be needed for some time.

G20 finance ministers give tax havens until March 2010 to cooperate on tax evasion or face sanctions.

September 24-25, 2009:

G20 leaders, finance ministers and central bank governors meet in Pittsburgh.

(Writing by David Cutler, London Editorial Reference Unit;)