Prince Rainier III of Monaco is presently in critical condition after suffering heart and kidney failure and continuing respiratory problems. His palace announced that his chances of recovery are 'slim.'

A statement issued by five doctors treating the prince described the 81-year-old monarch as being in 'precarious' health and 'hopes for a favorable outcome remain extremely weak.' They also indicated that 'active therapy' would continue at this time.

Rainier is Europe's longest serving monarch and has reigned since 1949. His son, Albert, 47, took over as regent on Thursday. This means that Albert will take over all official royal duties but has not yet taken the throne.

Albert is the only son of Rainier and his late wife, actress Grace Kelly. He also has two daughters, Princess Stephanie and Princess Caroline.

In the unlikely event that Rainier does recover, he could reassume the responsibilities of the crown. He has been hospitalized since March 7 and been in intensive care since March 22.