who was the prime minister of u.k. then?
H. H. Asquith
Asquith as prime minister
 his prime minister, H. H. Asquith, leader of the Liberal Party. 
at the beginning of world war i great britain Great Britain was a leading Allied Power during the First World War
H. H. Asquith David Lloyd George H. H. Asquith.
History of the United Kingdom during the First World War History of the United Kingdom during the First World War History of the United Kingdom during the First World War
Introduction Lloyd George as prime minister Asquith as prime minister
The war saw a move away from the idea of "business as usual" under Prime Minister H. H. Asquith,  and David Lloyd George (then a minister in the cabinet).  On 4 August, King George V declared war on the advice of his prime minister, H. H. Asquith, leader of the Liberal Party. Britain's basic reasons for declaring war focused on a deep commitment to France and avoidanc
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History of the United Kingdom during the First World War [SEP] Asquith as prime minister
On 4 August, King George V declared war on the advice of his prime minister, H. H. Asquith, leader of the Liberal Party. Britain's basic reasons for declaring war focused on a deep commitment to France and avoidance of splitting the Liberal Party. Top Liberals threatened to resign if the cabinet refused to support France—which would mean loss of control of the government to a coalition or to the Unionist (i.e. Conservative) opposition. However, the large antiwar element among Liberals would support the war to honour the 1839 treaty regarding guarantees of Belgian neutrality, so that rather than France was the public reason given.