This time, according to the Kremlin, the president's ailment is a bleeding stomach ulcer.

Just a few months ago he was hit by dizziness followed by pneumonia, his second bout in less than two years. And in November 1996, his first episode of pneumonia followed major heart surgery - a quintuple by-pass operation after a heart attack between during the presidential election in the summer of 1996.

If Boris Yeltsin were given marks for his health during this term in office, he would not score very highly.

Missing leader

Primakov: Would assume Presidency until elections

Unfortunately for Russia, just when strong, sensible leadership has been most needed, President Yeltsin's health has let the country down.

In the first half of 1998, after years of industrial decline stretching back before the collapse of the Soviet Union in 1991, things seemed to be looking up for the economy.

But, rather like the overly optimistic reports that Mr Yeltsin has been getting better, this proved a false diagnosis. In August 1998, the rouble collapsed, sending Russia into its worst economic crisis since the fall of Communism.

Recriminations

It is a hallmark of Russian thinking - as it was in Soviet times - that when the boss is away, the underlings refuse to show any initiative, for fear of losing their positions when the boss returns.

Indeed, whenever President Yeltsin has returned to his office in the Kremlin after an extended absence because of ill health, the first thing he has done is sack a number of his staff.

That's hardly conducive to having his staff take decisions the next time he is away.

Growing calls for change

The Communists and nationalists in the lower house of parliament, the State Duma, have long criticised Mr Yeltsin for hanging on to the reins of power when he has been incapacitated - they have tried unsuccesfully to have him impeached.

But now calls for the president to step down are being heard across the political spectrum. When Mr Yeltsin failed to show up in the Kremlin last week after the New Year break, the mayor of Moscow, Yury Luzhkov, formerly a strong Yeltsin supporter, criticised him openly.

A few days ago, the Kremlin was trying to play up a visit by President Yeltsin to France, due to take place at the end of January. The only trip many Russians will now want Mr Yeltsin to make is into retirement.