Adam Afriyie's plan to steer leadership-backed legislation on an EU referendum through Parliament has been criticised by fellow Tory MP James Wharton.
Wharton suggested the move would delay and even "kill" the private member's bill he introduced in July, and hoped Afriyie would "rethink" his approach.
He said: "We need to build as broad a base of support for the bill as we can if we are to get it through Parliament and the policy of a renegotiation, followed by an in/out referendum, is the right one to do that and the right one for the country.
"I hope MPs will decline to support it as the ultimate impact might well be to kill my bill, which would only help those who don't want any referendum at all."
More top news
The former footballer said he hopes speaking about his grief will help others who find it difficult to talk about their feelings.
Royal Marine Alexander Blackman has spent more than three years in jail since being convicted of murdering an insurgent.
There are believed to be less than 250 of the global population remaining due to poaching and loss of habitat.