Senior officials from Qatar have strongly denied claims the country is supporting terrorist groups in Syria such as Islamic State.
They told the BBC that Qatar had only provided support to moderate militants, in co-ordination with the CIA and other Western and Arab intelligence agencies.
Strict financial controls had been put in place, they added.
The comments come ahead of a visit to the UK this week by the Qatar's ruler Sheikh Tamim bin Hamad Al Thani.
Earlier this month of a number of MPs were reported to have questioned the UK's closeness to Qatar, amid the claims of the links to IS funding.
BBC security correspondent Frank Gardner says Qatar, a major investor in the UK through its sovereign wealth fund, has been stung by the allegations.
'Nothing to hide'
In the past, wealthy individuals in the emirate are believed to have made donations and the government gave money and weapons to hardline Islamist groups in Syria. Doha is also believed to have links to the al-Nusra Front, an al-Qaeda affiliate.
But officials, including Qatar's director of Intelligence, told the BBC the country had nothing to hide over its support for groups in Syria fighting President Assad's regime.
The BBC's Frank Gardner said the officials conceded that there had been constant shifts in allegiances in Syria's civil war and some people previously considered moderate had later joined hard line Islamist militias.
They said since Qatar's intelligence agency had taken over responsibility for its Syria policy in 2012, the new financial controls had been brought in and a number of suspect financiers had been arrested.
Since September, Qatar has been supporting the US-led military action against IS in Syria.
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http://www.bbc.co.uk/news/world-middle-east-29782291
