Media freedom has the power to transform societies and to change the course of history. Over the past year, across the Middle East and North Africa, ordinary citizens found their voices using social media and blogs. But freedom of expression continues to be repressed in many countries and some have seen a significant decline in media freedoms. Around the world, journalists, bloggers and others have been obstructed from doing their work by being harassed, monitored, detained, or subjected to violence.

Today, on World Press Freedom Day, we recognise the role the internet continues to play in strengthening freedom of speech across the globe. More importantly, as a pioneer of digital media and a supporter of freedom of speech, we pledge to defend this progress. This clear commitment features prominently in the Foreign Office 2011 Human Rights and Democracy Report, which is published this week.

Britain stands for universal human rights, the rule of law, democracy and freedom of expression. We fight for these values wherever they are under threat and, as demonstrated in our Human Rights Report, name those countries where the worst abuses take place. Britain is committed to being a strong global voice against restrictions of freedom of expression on the internet.

Digital and social media have changed the world, but that process of change presents new challenges. The existing framework of international human rights law - including the right to freedom of expression - is equally applicable online as it is offline. But the daily technological battle, as governments find new ways to block legitimate criticism, and protestors find new ways to escape their control, means the rules are constantly changing.

The overriding challenge is that 95% of the internet is owned by private companies, so to guarantee an open and innovative internet, governments must work with business, as well as with civil society, on how to safeguard and enhance online freedoms. This is why we took the decision to include internet-related companies at the London Conference on Cyberspace in November last year - which, in international diplomatic terms, was ground-breaking. A limited forum where foreign minister talked to foreign minister would not have worked - which is why we invited the practitioners at the front of the digital revolution.

So Britain is committed to helping governments, business and individuals to overcome threats to internet freedom. We are supporting businesses to enhance internet freedom through responsible commercial practice. Human rights could, for example, form part of a company's risk analysis prior to investing in a country.

We also know business is taking the lead itself. In the ICT sector, one tool available for companies to protect themselves is the Global Network Initiative (GNI). This is an effort by Microsoft, Google, Yahoo, human rights organisations, academics, and investors to ensure companies protect freedom of expression and privacy online through a set of voluntary principles.

In the great ideological battles of the last century, there was a debate about the nature, extent and value of freedom. The supremacy of the liberated individual triumphed over the ambitions of the authoritarian state. Internet freedom exists and is unstoppable - attempts to block sites and to stifle free debate will prove to be futile. The question for governments around the world is not how to repress free speech - online or offline - but rather how to engage and interact with their population. That is the internet of the future, and a central principle of Britain's ambition for individual freedom for all people.

The Foreign Office 2011 Human Rights and Democracy Report was published this week at www.fco.gov.uk/hrdreport