Mr Hague warned them that genetically modified food and cloning will become hot political topics in the years to come.

Speaking at a student conference in Westminster, Mr Hague also condemned Prime Minister Tony Blair for failing to put a moratorium on the sale of GM foods until their safety to people and the environment has been proved.

Hague: If we get these issues wrong we won't be able to put them right

"I hope the Labour Party will not, in search of political donations, have a policy which is not in the best interests of the country."

Mr Hague also spoke out against scientists experimenting with human cloning.

He said: "It is people playing with genetics. I instinctively feel there is something very seriously wrong with that and we don't know what it is going to turn into."

He added: "I am basically opposed to human beings playing God."

Tony Blair has rejected a moratorium on GM food

But Mr Blair refused, saying: "I think we do have to proceed on the best scientific evidence since we are also talking about something where the potentials are very great indeed, and it's important that we proceed logically and scientifically and not on the basis simply of prejudice of either side of the debate."

He added: "The worst way to proceed is to raise fears in the public mind before evidence is put before them."