G20 leaders cannot solve all of the world's economic woes on April 2, no matter how high British Prime Minister Gordon Brown builds expectations for a landmark financial summit that he will host in London.

As Angel Gurria, head of the Organisation for Economic Cooperation and Development, describes it: "There is no 'open sesame'. We're not talking about pulling rabbits out of hats."

G20 finance ministers made tentative advances during their preparatory talks at a countryside hotel south of London at the weekend, promising to raise the amount of funds available for emerging market economies that cry out for help.

Absent was the public bickering over economic stimulus versus regulation that had plagued the run-up to their session.

Beyond that, they rehashed and renewed many other pledges made when G20 leaders held their first summit on the global financial and economic crisis last November, saying free-wheeling hedge funds would no longer escape regulation.

What perhaps counts most right now, economists say, are two things - their joint commitment to do whatever it takes to keep the world economy afloat, and Washington's plans to tackle the toxic assets that started the crisis and will perpetuate it as long as they fester untreated on banks' books.

"We are left hanging on the hope that the US will finally find the magic bullet to restore transparency and confidence in the financial sector, and that they will do it soon," says Marco Annunziata, London-based chief economist at UniCredit.

In essence, financial markets where the trouble began have been looking for quick and easy fixes to a complicated mess.

Governments have already committed trillions of dollars to bank recapitalisation and debt repayment guarantees. Central banks have slashed interest rates and are pumping vast amounts of short-term funds into money markets to keep them functioning as commercial banks clam up.

Now governments are rolling out massive public spending programmes to try to shore up demand to ease the pain of what the IMF calls the Great Recession, the biggest predicted contraction in GDP since before World War II.

All that has kept the boat afloat while they tackle the hardest issues of all: repairing a system that went very, very badly wrong.

It is easy to say global problems require global solutions when banks, financial markets and businesses often operate on a worldwide basis. But governments operate within national borders - hence the attempts to cooperate via the G20, where the large economies of the industrialised and industrialising world with roughly 80 per cent of GDP are represented.

"One positive thing that can be said about this summit is the political leaders of the countries that more or less matter for the world economy are at least talking to each other," said Thomas Mayer, global economics specialist at Deutsche Bank.

Small as it sounds when millions are losing their jobs, talk is creating incremental change. Switzerland and several other countries responded to mounting international pressure in recent days by saying they would ease strict bank secrecy in some cases of suspected tax fraud.

"This is a quantum leap," Mr Gurria said.

The bottom line is that the G20 process, easy to pillory as all words and no action, is more of a process than an event. Meetings keep up the pressure for change and governments take away one idea or another to work on - mindful of the need as much as possible to pursue policies that will not be at the expense of others, or they could risk another Great Depression.

Things are inching forward on other fronts at the international level too, including commitments this weekend to regulate hedge funds and impose stricter controls on ratings agencies. But progress on tighter regulation and supervision of banks is slow.

"Let's hope that the victory over tax havens and hedge funds inspires them to eventually take on the big beasts, protectionism and the economic crisis," Mr Mayer said.

The challenge facing policymakers is doing what it takes in terms of emergency measures to stabilise banks and the economy, without losing sight of the need to move ahead on pledges to regulate and restructure a financial markets system that caused the trouble in the first place.

Thus the summit gets pulled between two objectives: the short-term goal of stabilisation of markets and the economy, and the longer-term drive to ensure the crisis isn't repeated.

For the short term, Unicredit's Annunziata says the weekend pledge to provide more funds for emerging market economies is extremely important as credit and investment flows to much of eastern Europe dries up.

On that front, the April 2 summit can be expected, some officials said, to announce that the International Monetary Fund, which has already committed close to $50 billion to economic rescues in Hungary and other countries, will be getting something in the region of $250 billion to double its firepower.

What is less clear is whether the summit will deliver one or two concrete steps to match what Gordon Brown said would be a "massive change" in oversight of financial markets.

Proposals on hedge funds, pay, ratings agencies

The G20 finance ministers laid out a broad framework for regulatory reform and repairing the financial system at meetings this weekend.

Following is a summary of recommendations in their communique for G20 leaders to consider at their financial summit in London on April 2:

• Hedge funds or their managers should be registered and disclose information needed to assess risks they pose to the financial system. Any financial institution or instrument that could pose a risk should have regulatory oversight.

• Pay and bonuses should adhere to the Financial Stability Forum's principles of sound practice.

• Capital reserves should be built up during good times and leverage limited in order to buffer financial firms during downturns. But in the current recession, capital should remain unchanged until recovery is assured.

• Credit ratings agencies should be registered, comply with the International Organisation of Securities Commissions code and have regulatory oversight.

• Off-balance sheet vehicles should be fully transparent; accounting standards improved notably on treatment of assets of uncertain value; there should be greater standardisation for credit derivative markets.

• Financial Stability Forum should be beefed up as part of strengthened international cooperation and it should conduct early warning exercises with the IMF.

US Treasury Secretary Timothy Geithner also said the FSF should be elevated as lead body for overseeing the global financial system, taking its place alongside the IMF, World Bank and World Trade Organisation.

Until now it has been an informal gathering of financial supervisors.

• On impaired assets, G20 leaders said a top priority for governments is to tackle toxic assets on bank balance sheets, now they have taken a range of steps such as injected bank capital, set up insurance schemes and are providing liquidity to money markets. In an attachment to the G20 communique, they released a set of principles to guide how each country handles assets of uncertain value.

The US said it plans to release its toxic asset plan before the April 2 summit.