Patience is wearing thin among some residents of the capital enduring another round of anti-government protests, with tens of thousands of opposition supporters showing no sign of giving up despite the onset of winter rain.

Huge crowds descended on Islamabad from various parts of the country a week ago, denouncing the government of Prime Minister Imran Khan as illegitimate and calling for him to step down.

It is the first concerted challenge that the cricket star-turned-politician has faced since he won a general election last year promising to end corruption and create jobs for the poor.

Khan has dismissed the calls to resign and his government, which the opposition says won power after a fraudulent election.

The military denies favouring any party saying it supports the constitution.

The protesters are occupying a large open area alongside one of Islamabad's main roads, the latest in a succession of drawn-out sit-ins over recent years, including one Khan himself led against the previous government.

"This is the third sit-in since 2014 in Islamabad - it has to stop if this country wants to progress," said office worker Ghazanfar Ali, 47.

The capital's sole public transport system, which runs by the protest site, has been suspended and Ali said he had to spend twice as much getting to work.

Student Zeeshan Azeem, 17, said the internet had been down at his home all week, which he blamed on government attempts to disrupt the protesters' communications.

"We're forced to travel a considerable distance from the protest site to use the internet," said Azeem, clutching his books as he headed home from school.

"When we complain to the service provider, they said they have down-graded the service on the government's instructions."

The government has not confirmed any such order but it is a regular tactic, and staff at providers have said they had been told to suspend services in some areas.

The protests are being led by one of the country's main conservative religious parties, with the support of the two main parties. The huge crowd is almost exclusively made up of bearded men, waving flags and chanting slogans.

They have set up a tent city with plastic sheets, and cook and rest when their leaders are not giving speeches. The mood has been cheerful and there has been no significant trouble.

The biggest problem has been the onset of cold rain.

Khan said on Twitter this week he had directed city authorities to assess what help could be provided for the protesters.

Copyright Business Recorder, 2019