Pope Francis Christmas
Pope Francis kisses a statue of baby Jesus as he leads the Christmas night Mass in Saint Peter's Basilica at the Vatican on 24 December 2015Reuters

World leaders are taking to the airwaves and social media outlets on Christmas day to address the people of their nation. With many reflecting on the harrowing events of 2015 – from deadly global terror attacks to the worst refugee crisis since the end of World War II – heads of state are delivering messages of hope and peace.

Queen Elizabeth II will deliver her message to the UK and Commonwealth countries at 3.00pm GMT today (25 December). She will say: "It is true that the world has had to confront moments of darkness this year, but the Gospel of John contains a verse of great hope, often read at Christmas carol services: 'The light shines in the darkness, and the darkness has not overcome it'."

Catholic leader Pope Francis took the opportunity to denounce materialism and said Christmas was a time to "once more discover who we are". He said: "In a society so often intoxicated by consumerism and hedonism, wealth and extravagance, appearances and narcissism, this child calls us to act soberly, in other words, in a way that is simple, balanced, consistent, capable of seeing and doing what is essential." The pope will deliver his traditional message later today from St Peter's Square.

Australian Prime Minister Malcolm Turnbull took the opportunity to thank defence and emergency service members – many of whom will be spending Christmas away from their families. He also asked the public to think of those less fortunate. "We should also think of those less fortunate this Christmas. Poverty, loneliness, illness, the loss of loved ones – these shadows hang heavier at Christmas," he said. "We can lift some of those shadows by sharing our love with others — beyond our family and close friends."

Iran's President Hassan Rouhani expressed a message of congratulations to Christians on 24 December and spoke of greater cooperation and peace between nations. He said: "I hope that we would see, through efforts and more cooperation between [world] countries, restoration of daily-growing peace and security, elimination of discrimination and eradication of terrorism across the globe."

After an inconclusive election result, Spain's King Felipe VI called for "national cohesion" as growing calls from independence in Catalonia. In a televised address he said: "Political plurality, expressed at the ballot box, without a doubt offers different sensitivities, visions and perspectives; and it involves a way of exercising politics based on dialogue, consensus and commitment."

Narendra Modi and John Key, prime ministers of India and New Zealand respectively took to Twitter to wish people a merry Christmas.