World leaders at the G8 summit have issued a united condemnation of the attacks on London that injured many people, and killed at least two.
They said violence would not halt the summit, where talks would continue "in the interests of a better world".
It was read by UK Prime Minister Tony Blair who is travelling to London for police briefings before returning to Gleneagles this evening.
It called the blasts "an attack on civilised peoples everywhere".
Earlier, Mr Blair said it was the will of all the G8 leaders that the summit should continue in his absence.
It was "particularly barbaric" that this should occur when people are meeting to tackle poverty, he said.
Mr Blair said it was "reasonably clear" the explosions were designed to coincide with the opening of the G8.
The joint condemnation came from all the countries represented - including China, India and African states - and international agencies like the World Bank and International Monetary Fund.
It has now been announced that Foreign Secretary Jack Straw will chair the G8 summit while Mr Blair is in London.
Earlier, the US and UK leaders called for a new consensus on how to tackle climate change as the opening session of talks got underway.
G8: PROGRESS SO FAR
G8 nations agreed to full debt cancellation for 18 countries, while African countries call for debt relief for all Africa
EU members have pledged to reach a collective aid target of 0.56% of GDP by 2010, and 0.7% by 2015
President Bush proposed doubling US aid to Africa over the next five years to $8.6bn (£4.8bn)
No deal yet made on lifting trade barriers
No progress made on climate change yet - the US has said it won't cut emissions but will look at clean technologies
They said it was time to replace a focus on Kyoto-style curbs on greenhouse gas emissions with research into clean technology.
President Bush said fast-developing nations must take a role, and welcomed India and China's attendance at the G8.
Along with climate issues, G8 leaders are due to discuss global trade.
With more than 10,000 police deployed, the summit is at the centre of one of the biggest security operations in UK history.
"Now is the time to get beyond the Kyoto period and develop a strategy forward that is inclusive of the developing nations," said US President George W Bush.
WHAT IS THE G8?
Group of eight major industrialised states, inc Russia
Canada, France, Germany, Italy, Japan, Russia, UK, US
Originally set up to discuss trade and economic issues
Now leaders discuss global issues of the day
2005 Summit agenda
UK Prime Minister Tony Blair said there was "no point in going back over the Kyoto debate" and it was preferable to "bring people back into consensus together" on global warming.
For many protesters and observers, the G8 summit is a defining moment in current world politics, amid increased calls for the world's richest countries to act now to help the world's poorest.
Demonstrations and Live8 concerts over the last four days sought to highlight the need for action on the issues of African aid, trade and climate change.
In other developments:
- Police encircle an eco-camp housing 1,000 protesters in Stirling.
- 160 arrests as police and protesters clashed on Wednesday.
- Financier George Soros says the US is in "total denial" over climate change.
- UK Chancellor Gordon Brown hails US acceptance that "human activity" is causing global warming
- Mr Blair says there is "no point going back over the Kyoto debate.
After the climate change talks, the G8 leaders are timetabled to discuss Middle East tensions, and hear from James Wolfensohn, the international envoy on Israel's pull out from Gaza.
African aid and trade will dominate the talks on Friday.
Some countries, notably Germany, have pressed for high oil prices and global economic imbalances to have a bigger place in the talks.
Frictions on climate change have emerged as high-level officials from the G8 nations have battled to hammer out an agreement ahead of the talks.
France is pushing for an agreement to reduce greenhouse gas emissions, whereas Mr Blair has called for "sensible compromise" and backed the US focus on fuel-efficient technology.
Some critics think the UK is too willing to seek a compromise. International financier George Soros said "looking for common ground" would "merely...water down the seriousness of the situation".