Tory MP questions chairman's role on EU vote donations
Tory chairman Lord Feldman has been accused of urging donors to give money to the campaign to stay in the EU.
Steve Baker, chairman of Conservatives for Britain, said Lord Feldman had admitted he directed donors to Britain Stronger in Europe in his "spare time".
Mr Baker said other cabinet ministers should now be allowed to help Vote Leave.
The Conservative Party said Lord Feldman would direct donors to the both the "in" and "out" campaigns.
It follows a row over whether cabinet ministers should be allowed to campaign for exit if, as expected, David Cameron gets behind the remain campaign.
In an article for The Daily Telegraph, Steve Baker wrote: "Lord Feldman, our chairman, has confirmed to me that he has directed donors to give money to the pro-EU BSE (Britain Stronger In Europe) campaign in a personal capacity and in his spare time.
"He also tells me that he will point people in the direction of the Vote Leave campaign, but they are yet to receive a referral from our party chairman.
"Lord Feldman is a member of the political cabinet... now he has admitted this new part time role, shouldn't the Prime Minster allow other cabinet members to help Vote Leave in their spare time?"
In a statement, the Conservative Party said: "Donors will call Lord Feldman to ask how to support both the 'in' and 'out' campaigns.
"Lord Feldman will simply direct them to the relevant people. It is up to the individual donors themselves to if they then choose to contact or support either."
BBC Political Correspondent Chris Mason said the spat offered an "insight into how carefully the prime minister has to manage the build up to the EU referendum - so it doesn't tear his party apart".
David Cameron is aiming to come back from a summit in February with a package of reforms to Britain's relationship with the EU, which he will then put to the public in a referendum.
But speculation is rife about whether senior figures in his cabinet will say the reforms are not good enough and join the campaign to get Britain out of the EU.