General Sir Patrick Sanders is the new head of the British Army.
Defence Secretary Ben Wallace announced in February that the Queen had approved the appointment.
Gen Sanders took over from the previous Chief of the General Staff, General Sir Mark Carleton-Smith, and said in February he was "deeply honoured" to be appointed "at such a pivotal time for the future of the British Army".
"The Russian invasion of Ukraine is a stark reminder that the world is becoming increasingly dangerous and uncertain with war on land coming to Europe for the first time in decades," he said.
"The British Army will play its part in defending the UK and our allies as we have for centuries.
"I started my career in the Army, it remains the bulwark of our defence and I am acutely aware of the great responsibility I am taking on."
One of the first tasks for the new Chief of the General Staff was to meet with British Army Sergeant Major Carney – whose job is to represent the views of soldiers – and discuss the future of the British Army and how serving personnel and civil servants can be supported.
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General Sanders started his military career in 1986 and was commissioned into The Royal Green Jackets.
He spent his early career on Regimental Duty in Germany, Norway and the UK, before commanding at company, battalion, brigade and divisional level – including on operations in Northern Ireland, Kosovo, Bosnia, Iraq and Afghanistan.
His staff appointments have all been in operational and strategic roles, including as Policy/Military adviser for the Commander of Coalition Forces in Iraq in 2003 and 2004, Head Operations (Military) and Assistant Chief of Defence Staff (Operations) in the Ministry of Defence.
He was promoted to General in May 2019 before taking over as Commander Joint Forces Command, managing the organisation's move to Strategic Command.
Mr Wallace said Gen Sanders, in his former role as Commander of UK Strategic Command, had played a key role in shaping the military's future "by reflecting the new and emerging threats posed by cyber and 'greyzone' warfare".
"Gen Patrick is an exceptional military leader and the Army will benefit greatly from his knowledge and experience," he said.
Mr Wallace added that Gen Sir Patrick takes up the role at a critical time for the Army.