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."
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Largely dry night, but showers set to spread in from the west during tomorrow.
Any lingering showers will ease, to leave a dry night with plenty of clear spells. Cloud thickening from the west, but staying dry.
Crowds of people gathered in Sandringham on Sunday to catch a glimpse of Princess Charlotte as she arrived for her official christening.