Pakistan clamps down on protests amid fresh fears of a military coup

The government is trying to stop a march by lawyers from reaching Islamabad

Pakistan's army was put on stand-by yesterday to deal with growing demonstrations against the government, which are due to reach a climax in the capital, Islamabad, tomorrow. Divisions within President Asif Ali Zardari's administration were underlined by the abrupt resignation of a senior minister.

The government has already cracked down on lawyers who have been marching towards the capital, where they plan to hold a rally to demand the reinstatement of a one-time chief justice, ousted by Pervez Musharraf, the former president. More than 1,000 people have been arrested. The government also closed a television channel, Geo News, because of its coverage of the confrontation, but this led the Information Minister, Sherry Rehman, to quit in protest. Her departure is an embarrassment to Mr Zardari since Ms Rehman was a friend of his late wife, Benazir Bhutto.

There has also been intense international pressure on Mr Zardari and his Pakistan People's Party (PPP) to reach a compromise with the marchers. Yet despite speaking by phone to Britain's Foreign Secretary, David Miliband, and the Obama administration's regional envoy, Richard Holbrooke, among others, he does not appear to have done so.

Among those throwing their weight behind the march is the former prime minister, Nawaz Sharif, the head of the Pakistan Muslim League-N (PML-N) and a man whose relationship with Mr Zardari has in the past been sour. The situation has worsened in recent weeks after the Supreme Court ruled that Mr Sharif and his brother, Shahbaz, were ineligible to stand for elected office. This forced Shahbaz Sharif to stand down as head of the provincial government in Pakistan's largest province, Punjab, after which Mr Zardari ordered that it be ruled by the central government.

Mr Zardari has been urged to seek an agreement with Mr Sharif that would defuse the fears of some observers that Pakistan's military could decide to intervene. The government announced yesterday that it would seek a Supreme Court review of the ruling barring the Sharif brothers from office, but this apparently conciliatory gesture was rejected by their party as an attempt to divert attention from the "long march" protest.

In an effort to block the lawyers' progress, many senior figures have been prevented from leaving their home cities. Ali Ahmed Kurd, the head of the Supreme Court bar association, was confined to Quetta on Friday, but said: "The long march can't be stopped. So far, our attitude is soft, but we can change our strategy. When one path is blocked, God opens 100 others."

Geo News has been taken off the air before – for three months after Mr Musharraf imposed a state of emergency in November 2007. "We were not expecting this from a democratic government," said Azhar Abbas, director of the television channel. "It was easy to expect such actions from military dictators."