Britain's David Cameron raised the issue of funding for extremist groups at a meeting with the emir of Qatar in London on Wednesday, the prime minister's office said.

Qatar is part of the US-led coalition against the Islamic State group, but has been accused of allowing money to be funnelled to Islamic State jihadists, something it denies.

In a meeting with Sheikh Tamim bin Hamad al-Thani, Cameron welcomed a new law against terrorism funding and "looked forward to the swift implementation of these new measures", a statement said.

The law, passed in mid-September amid Western concerns over extremist funding, is aimed to prevent charities involved in politics using their status to send money to groups of concern.

"They discussed the role both countries are playing in the coalition to tackle ISIL, and the importance of all countries working to tackle extremism and support to terrorist organisations," the prime minister's office said.

"They also agreed that both countries should do more to share information on groups of concern."

The prime minister was earlier pressed in parliament whether he considered Qatar "permissive jurisdiction for terrorist finance".

Cameron also raised the 2022 World Cup, and "offered to share the UK's expertise in the construction industry" in preparations for the event.

The awarding of the tournament to Qatar has been dogged by allegations of corruption and rights groups have criticised worker conditions and a high death rate in construction.

The oil and gas rich gulf state is a big investor in Britain and owns landmarks such as the country's tallest building the Shard and department store Harrods.

Recent Qatari investments in Britain amount to over £20 billion ($32 billion, 25.3 billion euros), the statement said.