By Oliver Hotham
Sunday's presidential elections in Russia need further investigation, William Hague has said.
Vladimir Putin claimed victory on Sunday evening, with official results saying he won with over 60% of the vote.
But international observers monitoring the election said that "voter's choice was limited, electoral competition lacked fairness and an impartial referee was missing".
They also claimed the vote count remained suspect due to "procedural irregularities" at a third of polling stations.
Mr Hague noted the report by the Organisation for Security and Co-operation in Europe which said that, while candidates we allowed to campaign freely, conditions were clearly skewed in favour of winner Vladimir Putin.
"Overall, while the Mission gives a positive assessment of voting on election day, it identifies problems with counting at some polling stations, unequal campaign conditions, and limitations on voter choice. These issues should not be overlooked," the foreign secretary said.
"A Russia with greater political freedoms, including the registration of political parties, freedom of assembly, and freedom of the media is in the interests of Russians and of the wider world.
"All allegations of electoral violations should now be thoroughly investigated."
The foreign secretary is continuing the British government's policy of avoiding too openly criticising the Kremlin – a policy former foreign secretary David Miliband called "respectful disagreement".
The British government's criticism of Mr Putin has in the past been limited by Britain's heavy reliance on Russian natural gas.
Wikileaks cables released in 2010 reveal American diplomats regard Putin's Russia as a "mafia state" where "one cannot differentiate between the activities of the government and organised crime groups".