The Department of Agriculture has issued a warning about the risk of forest fires.

It has issued an Orange alert - the third highest of four warning levels - which will remain in place until the end of the week.

The department issued the warning because of high pressure weather conditions.

Coillte's communications manager Pat Neville has urged the public to be vigilant.

He said the highest risk of forest fires is at this time of year, when last year's vegetation has not fully decomposed and become dried out.

Speaking on RTÉ's Morning Ireland, Mr Neville said that most forest fires do not start naturally and we all have an important role to play in preventing them.

Simple acts such as lighting a campfire or having a barbeque can have potentially catastrophic effects, he added.

Six hundred hectares of forest were damaged by fire last summer, Mr Neville said:

"Most forest fires don't start naturally. And it's probably a combination of careless behaviour, in some cases, reckless or even malicious behaviour.

"So all of us have a very important role in protecting forests and people and the environment - habitat and species - from forest fires. Very simply people lighting a campfire or having a barbeque in a forest can have very catastrophic effects, if the vegetation lights up," he added.

There is also a reminder that it is illegal to burn vegetation on uncultivated land between March and the end of August with specific rules about how landowners may have a burn.

The warning comes a month after a gorse fire in Co Donegal threatened homes and businesses.