Support for Islamic extremism and suicide bombings is down in countries with significant Muslim populations, according to a new survey by the Pew Research Centre.

The survey, released this week, shows that support for suicide bombings has dropped by 16 per cent in the Palestinian territories over the past year - from 62 per cent to 46 per cent.

The report also found an increasingly negative view of extremist groups - including al-Qaeda, Hamas and Hizbollah - across the Middle East.

However, 46 per cent of respondents in the Palestinian territories said that suicide bombing is often or sometimes justifiable in order to defend Islam.