MOSCOW (AP) _ President Boris Yeltsin stayed home today, nursing a respiratory infection that forced him to cut short a foreign trip and revived concerns about his ability to govern Russia.

Yeltsin was spending the day at his country residence outside Moscow, and will probably not go into the office all week, said his spokesman, Dmitry Yakushkin.

However, Yeltsin's condition was stable, Yakushkin said.

Doctors insisted Monday that Yeltsin fly home from Central Asia a day ahead of schedule because he was suffering from an upper respiratory infection and had a mild fever of 99.3 degrees.

They said Yeltsin was being treated with antibiotics and there were no plans to hospitalize him.

Yeltsin, 67, has a history of health problems, including quintuple heart bypass surgery two years ago, so whenever he gets sick there is a flurry of speculation about his ability to function.

The president insists he has no major illness and plans to serve out the remaining two years of his term. Yakushkin reiterated today there was no talk about an early resignation.

He and other aides sought to play down the seriousness of Yeltsin's illness.

``Don't panic, Dad is OK,'' Yeltsin's daughter Tatiana Dyachenko, who is his official image adviser, told the Kommersant business newspaper.

Yakushkin said Yeltsin's doctor, Sergei Mironov, confirmed that the president was suffering from tracheal bronchitis.

``He must stay in bed like any other person,'' Yakushkin said. ``However, knowing the president's character, he is certain to start working with documents and making phone calls to Russian politicians as well as foreign leaders in view of the current situation in Kosovo.''

But the Nezavisimaya Gazeta newspaper said in a front-page editorial that Yeltsin's condition suggests he has something worse than a cold.

It said his absence from the Kremlin during Russia's economic crisis ``amounts to a state catastrophe'' and called on Yeltsin to immediately surrender most of his powers to Prime Minister Yevgeny Primakov.

Yakushkin dismissed newspaper speculation, citing doctors, that Yeltsin is suffering from complications following his bypass surgery and possibly even Alzheimer's disease.

``It's unethical for a doctor to comment on someone's health without seeing the patient,'' he snapped.

A Communist lawmaker also called for ``an urgent medical check ... on the Russian president's health'' to determine whether he is fit to remain in office, the Interfax news agency said.

``Yeltsin's obvious inability to perform his functions is damaging Russian state authority, as power is being misused by the clique close to the president,'' said Viktor Ilyukhin, chairman of parliament's security committee.

The health of the president, who is also commander-in-chief of the Russian military, ``is a direct threat to the country's national security and a factor of serious concern regarding Russia's nuclear weapons,'' he said.

Communist leader Gennady Zyuganov said the Russian parliament's upper chamber may demand Wednesday that Yeltsin step down.

Newspapers gave a detailed description of Yeltsin's weaknesses and his erratic behavior on the trip to the former Soviet republics of Uzbekistan and Kazakstan _ his first foray abroad since a visit to Britain in May.

The president stumbled when he arrived Sunday in Uzbekistan's capital of Tashkent and had to be supported by Uzbek President Islam Karimov. He canceled other public events.

At a state dinner that night, Yeltsin made rambling remarks, expressing his satisfaction with local ``facilities and stores'' he never inspected, the daily Kommersant reported.

On Monday, ``the president didn't seem to understand that he wasn't in Moscow,'' Kommersant said, saying he called aides and spoke as though they were late for work at the Kremlin.

He turned up more than an hour late for talks with Uzbek officials, making incoherent remarks interrupted by a bad cough and abruptly cutting short a news conference.