Conservative Central Office tried to gag Eurosceptic MPs from publicly lobbying their local party members to vote “leave” – unless a pro-EU supporter was lined up to disagree with them.

In a letter sent to all the party’s Association Officers the Conservatives’ Director of Organisation warned that they would be breaching party rules if they allowed their local MP free reign to speak out against the EU at their annual general meeting. Instead, the letter said, if their MP planned to use the event to talk in favour of Brexit, the association must ensure that “the opposite view is equally strongly advocated”.

But the letter, which was sent out earlier this month, sparked a furious response from Tory MPs who accused CCHQ of trying to “gag” them. As a result of the pressure, CCHQ backed down and said MPs were allowed to make their views clear at association annual general meetings. The party told MPs that the letter had been a misunderstanding and that it was never intended to gag MPs from making their positions on the EU clear to their local party members.

However, any referendum events held by associations will still be required to have speakers from both sides.

The letter, which was copied to regional party officials, came from Alan Mabbutt, the Tory Director of Organisation. “I have been asked about the Party’s position with regard to Members of Parliament or Members of the European Parliament addressing Association AGMs,” he wrote. “I am aware that an MEP has asked to talk specifically about the forthcoming Referendum.”

He then added: “Associations may wish to hold meetings of members about the Referendum to which both sides of the argument should be put. If, therefore, a view is to be expressed by a speaker at your AGM, you should ensure that the opposite view is equally strongly advocated at the meeting.”

One MP whose local party received the letter said it had sparked considerable anger.

“The idea that CCHQ was going to stop me speaking to my own party was outrageous,” he said.

“We’ve got our AGM coming up and I was going to make my views very clear. This letter seemed to suggest that they would need to get someone to oppose me, which was crazy.”

The Conservative Eurosceptic MP Sir Edward Leigh described the situation as “ridiculous”.

“It is clearly an absurd letter but I have to say that nobody is going to take a blind bit of notice,” he said.

“Some bureaucrat is Central Office has clearly decided that it was a good idea to try and impose the party’s board’s neutrality in the referendum on constituency associations. But it is ridiculous to expect MPs to stay silent.”

It is understood that the letter was the result of a decision last year by the Conservative Party board to stay neutral.The decision means that neither Leave or Stay campaigners will be able to call on the resources of the party. In addition, local associations are expected to take a neutral stance. However, individual party members are allowed to campaign on either side.

A source on the 1922 Committee that represents Conservative backbench MPs said that the issue of the letter had been raised with them.

“We were told when we were asked that it was a misunderstanding and that there would be nothing to stop individual MPs stating their case to their local associations,” they said.