Britain's Queen Elizabeth has formally opened the Commonwealth Heads of Government meeting in London. It's the first time Commonwealth leaders have met since Britain voted to leave the European Union. The summit offers the British government a platform to promote its post-Brexit trade agenda. CGTN's Kate Parkinson reports.

A 53-gun salute - representing the 53 members of the Commonwealth - marked the official opening of the Heads of Government Meeting in London.

While in the ballroom of Buckingham Palace, Queen Elizabeth welcomed the Commonwealth leaders, telling them that the group is now stronger than ever.

QUEEN ELIZABETH II BRITISH MONARCH "We seem to be growing stronger year by year. The advantages are plain to see - an increasing emphasis on trade between our countries is helping us all to discover exciting new ways of doing business."

Issues under discussion at the two-day summit will include climate change, security and trade. British Prime Minister Theresa May told the leaders the summit would tackle some of the biggest questions of the 21st Century.

THERESA MAY UK PRIME MINISTER "How we support our most vulnerable member states as we tackle climate change and improve the health of our oceans, creating a more sustainable Commonwealth. How we developed through trade pushing back against protectionism for a more prosperous Commonwealth. How we respond to threats to the rules based international order and from cyberattacks creating a more secure or Commonwealth."

Brexit is not on the formal summit agenda but, on the sidelines and during informal moments, British officials will likely be trying to steer conversations towards post-Brexit trade deals.

As it prepares to leave the European Union, Britain is hoping to secure new free trade agreements. Key targets among Commonwealth nations include Canada, New Zealand, Australia and India.

On Wednesday, Theresa May met with Indian Prime Minister Narendra Modi to talk trade and signed off on a series of commercial agreement worth up to one billion pounds.

KATE PARKINSON LONDON "As one of the world's fastest growing economies, the benefits of securing a post-Brexit trade deal with India is clear. But the idea that the Commonwealth will be able to equal the EU as a trading partner is widely dismissed by experts, as is the notion that striking new deals will be easy. Kate Parkinson, CGTN, London."