Foreign Secretary William Hague has rejected claims he has lost his "mojo" and is ready to quit his job.
The politician has faced questions about his commitment to front-line politics amid criticism of his handling of the Libyan crisis.
Senior Liberal Democrat Sir Menzies Campbell has openly questioned Mr Hague's dedication to the job.
Sir Menzies said: "I am not sure just how enthusiastic he is about this business. It is very, very hard... It is a very, very demanding job."
Challenged about his commitment, Mr Hague fuelled speculation by saying only that he would remain in the job for "an extended period of time".
Now the Foreign Secretary has sought to end speculation about his future and Prime Minister David Cameron's support for him.
Mr Hague said: "If some of the people who write about mojo came with me for a week, they would drop dead on their feet.
"The Prime Minister is extremely supportive (of me) and so are the vast majority of Conservative MPs. People had better get used to the idea."
Mr Hague was criticised over the botched SAS mission to make contact with Libyan rebels and the slow start to the evacuation of British nationals.
Asked whether Mr Hague's position in Government was under threat, Mr Cameron's offcial spokesman said he was not planning a Cabinet reshuffle "any time soon".
The Foreign Secretary said he had given up "lots of things I love doing" - like writing, business and playing the piano - to return to frontline politics.
"I wouldn't give up all those things and come back into politics because I wasn't interested in it," he told The Sunday Telegraph.
He added: "There were two reasons I came back into politics - to support David Cameron and to serve the country.
"I am not walking away from those things. People had better get used to the idea."
Source - Yahoo.