Three-time prime minister Nawaz Sharif arrived back in Pakistan Saturday after four years of self-imposed exile, primed to make a political comeback ahead of elections.

The South Asian nation is facing overlapping security, economic and political crises ahead of polls already pushed back to January 2024, with Sharif's primary opponent, the fiercely popular Imran Khan, languishing in jail.

Sharif spent the past several days in Dubai and left on a chartered flight packed with journalists, touching down in the capital Islamabad around 1:30 pm (0830 GMT) according to local media.

"We are completely ready for elections," he told reporters before his flight took off.

"Our country which should have been at the heights of prosperity has really gone backwards," he said. "How did we get here? Why did it come to this?"

Analysts say Sharif's return has likely been brokered by the powerful military establishment, which cracked down on Khan's party after their relationship soured as he was ousted last year.

Sharif will travel onwards to the eastern megacity of Lahore, where supporters were already gathering for a welcome home rally with streets shrouded in green and yellow party banners, posters and flags.

More than 7,000 police have been enlisted to control crowds expected at the Greater Iqbal Park where his homecoming speech is due later, according to a senior officer on site.

"I'm here to welcome my leader. The inflation is very high and poor people are desperate," said 18-year-old Razi Ullah. "God has given him a chance to come back and turn things around. He's done it before."

- Return of the kingpin -

Sharif's return has been touted for months by his Pakistan Muslim League-Nawaz (PML-N) party, whose leaders hope Sharif's political clout and "man of the soil" swagger will revive its popularity flagging amid an economic backslide.

"I am a poor man, I expect only one thing from Nawaz Sharif: that he brings down inflation," said 50-year-old Umar Sabir who travelled over 250 kilometres (155 miles) to attend the rally.

But the former leader has a conviction for graft and an unfinished prison sentence hanging over him.

Earlier this week, the Islamabad High Court granted protective bail to Sharif until Tuesday, removing the threat of immediate arrest when he lands back in the country.

Sharif has been prime minister three times, but was ousted in 2017 and given a lifetime disqualification from politics after being convicted of corruption.

He served less than a year of a seven-year sentence before getting permission to seek medical care in Britain, ignoring subsequent court orders to return during former prime minister Imran Khan's government.

His fortunes changed when his brother Shehbaz Sharif came to power last year and his government oversaw changes to the law, including limiting the disqualification of lawmakers from contesting elections to five years.

But the short reign of the coalition led by PML-N also coincided with a stint of runaway inflation and a currency reserve crisis that brought the nation to the brink of default.

- 'Lion of Punjab' -

Legal hurdles blocking Sharif from power are likely being removed as part of a backroom deal between his party and the army, said analyst Zahid Hussain.

"There was some sort of arrangement with the military establishment; without that he wouldn't have decided to come back," he told AFP.

Often draped in a red Gucci scarf, Sharif has seen his political fortunes rise and fall on his relationship with Pakistan's powerful military establishment –- the country's true kingmakers.

Politicians in Pakistan are often tangled in legal proceedings that rights monitors say are orchestrated by the powerful military, which has ruled the country directly for more than half of its history and continues to enjoy immense power.

Fans call him "the Lion of Punjab", the eastern and most populous province where his support is strongest, and he is known to parade big cats at extravagant political events drumming up support.

But he faces the tough task of winning over an electorate weary of dynastic politics and a young population that has been captured by Khan's social-media-savvy party. 

"Sharif's key challenge is first to establish himself and his party as viable options to replace Imran Khan, who is already popular, and secondly to turn around the economy," said political analyst Ayesha Siddiqa.

Pakistan is currently being led by a caretaker government in the runup to elections.

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