Prime Minister Tony Blair is "fit, fine, in good spirits and 100% recovered" after hospital treatment for an irregular heartbeat, his official spokesman has said.
Mr Blair is now back in Downing Street
Mr Blair, who is under doctor's orders to rest for 24 hours after his heart scare on Sunday, is back behind his desk at Number 10, although "not working at full throttle", the spokesman said.
Foreign Secretary Jack Straw gave a statement to the House of Commons on the EU summit in place of the prime minister later on Monday, but Mr Blair is set to resume his normal schedule from Tuesday.
He will attend his regular audience with the Queen, and on Wednesday will return to question time in the House of Commons and give a speech on public services.
He will hold his regular monthly press conference on Thursday after chairing a meeting of the cabinet. He will then set off on a regional tour.
Mr Blair, 50, has never suffered heart problems before but was taken to London's Hammersmith Hospital on Sunday, after complaining of chest pains at his Chequers residence and first going to Stoke Mandeville Hospital.
Doctors diagnosed supra ventricular tachycardia - a condition which causes heartbeat irregularities and shortness of breath - and ordered the father-of-four to rest for a day.
BLAIR'S HEART PROBLEM
1: Tony Blair's condition, supraventricular tachycardia, is a non-life threatening heart rhythm disturbance caused by rapid electrical activity in the upper heart (the atria)
2: The same condition can affect the lower heart (the ventricles) as ventricular tachycardia - usually a sign of underlying heart disease
He was kept in hospital for nearly five hours, was sedated for 20 minutes and treated with a procedure called cardio version, which uses a small electric shock to make the heartbeat return to normal.
Mr Blair's official spokesman told journalists at Monday's lobby briefing the treatment had been "completely successful" and his health had suffered no lasting damage.
"He is fit, fine, in good
spirits and 100% recovered," the spokesman said.
"I have seen him this morning and I have to say, if I hadn't known that he
had been in hospital, I wouldn't have known from seeing him this morning.
"He has been told to take it a bit easier for today, which is why Jack Straw
is making a statement, but he is holding meetings in Downing Street as usual."
The spokesman said Mr Blair, who "takes lots of exercise" and "looks after himself", had been treated for "a relatively minor condition".
His appetite for the job was undiminished and there was no reason for the condition to recur, although he will probably see another doctor in the next few weeks.
"This appears to be one of those things that affects a comparatively large
number of people. It's nothing that comes even close to a serious cardiac
problem," the spokesman added.
Health Secretary John Reid said there was no reason for anxiety as the prime minister was "fine and fit".
"There is no reason at all why he can't continue just as he's done before as prime minister," added Dr Reid.
Conservative leader Iain Duncan Smith said his thoughts were with Mr Blair and his family as he wished the prime minister a speedy recovery.
Mr Blair has been under a great deal of stress in recent months, particularly after the strains of the war in Iraq.
But experts said the condition was more likely to be something that simply affected some people rather than others, instead of being linked to stress.
Dr Duncan Dymond, consultant cardiologist at Barts Hospital, London, told BBC Radio 4's Today programme: "In the grand scheme of things, it's a fairly minor condition - high in nuisance value but low in gravity.
"It can be very frightening for people when it happens, particularly when they don't know what it is."
He said it could happen to healthy people, and once treated was "compatible with a completely normal quality and quantity of life".
Dr Dymond said Mr Blair should have a couple of days rest, but added: "It's by no means set in stone that he will have another attack and there's no real reason for him to stop playing tennis or stop being prime minister based on this."
There have been widespread goodwill messages to Mr Blair from the world of politics in Britain and elsewhere.