Sharif flying home to Pakistan

By Sophie Walker

LONDON (Reuters) - Nawaz Sharif, the exiled former prime minister of Pakistan, left London on Sunday on a flight home to Islamabad where President Pervez Musharraf has threatened him with arrest.

Sharif boarded Pakistan International Airlines flight PK-786 to Islamabad at London's Heathrow airport, said a Reuters reporter who was also on the flight.

The plane had been scheduled to leave London at 8 p.m. (1900 GMT), but takeoff was delayed when an elderly passenger, not part of Sharif's group, suffered a suspected heart attack.

Paramedics took the man off the plane and it eventually took off around an hour and 40 minutes behind schedule, airport officials said.

Sharif, who was overthrown by Musharraf in a 1999 coup, is hoping to capitalize on public unrest at home and end the military leader's rule -- despite an appeal from Saudi Arabia to stay away for the sake of stability.

"I'm feeling great," Sharif told reporters as he prepared to get on the plane. Uniformed British police escorted him through a crowd of supporters on his way to the flight.

"I have a duty, I have a responsibility, I have a national obligation to fulfill at all costs and that is democracy," he added.

SUPPORTERS DETAINED

Pakistani authorities have tightened security at Islamabad's airport and have detained more than 2,000 of Sharif's supporters.

Sharif plans to lead a procession the 300 km (200 miles) from Islamabad to Lahore, the capital of Punjab province, and is expected to draw huge crowds -- the last thing Musharraf wants as he prepares to try to secure another term in a presidential election.

Musharraf sent Sharif to Saudi Arabia in 2000 as part of what the government says was an agreement that Sharif would stay in exile for 10 years. In return he avoided a life sentence on hijacking and corruption charges.

The Supreme Court said last month that Sharif had the right to return and the government should not try to stop him.

"I don't expect that Mr. Musharraf will go against the decision of the Supreme Court or take any action which is violative of the Supreme Court verdict because that would amount to a very serious contempt," Sharif told reporters on the plane.

"My ambition is very clear, I have to take Pakistan back to the rule of democracy, because unless we have this, we will continue to be in a state of mess as we are today."

The flight had been scheduled to arrive in Islamabad at around 0740 local time (0240 GMT) on Monday.

(Additional reporting by Paul Majendie in London)