Mr Brown has just concluded the G8 summit in L'Aquila, Italy
Gordon Brown is a "knackered" prime minister and should take a month's holiday, a Labour backbencher has said.
Austin Mitchell, MP for Great Grimsby, wrote in the Parliamentary House Magazine: "He should go away for a month and come back reinvigorated."
Mr Mitchell, who said he also made the comments directly to Mr Brown, added: "A knackered PM makes bad decisions."
In the same magazine, former deputy prime minister John Prescott said Mr Brown was "the best man for the job".
In the article, Mr Mitchell said the prime minister needed a gifted press secretary to turn around his image.
He wrote: "Gordon needs a press secretary of genius.
"Bernard Ingham created Margaret Thatcher and Alastair Campbell made Tony Blair.
"They did it by joining the dots, filling in the blanks, building the image and turning fragile humans into decisive Supermen."
He added: "Gordon has no one like that. So his frailties are not concealed and his indecisiveness gets out."
But in his article, Mr Prescott attacked Labour MPs accused of hoping to replace Mr Brown.
He wrote: "Some of those others seeking to be prime minister? Excuse me if I laugh.
"Stop complaining, start campaigning."
In a comment directed at the former Europe minister Caroline Flint, who resigned criticising Mr Brown's attitude to women, Mr Prescott added: "People resigning and saying, 'I'm only window dressing'.
"Is that what politics has got to? It is unforgivable."