The Taliban government will face nationwide protests if it fails to reopen girls' secondary schools within a week, women's rights activists in Afghanistan vowed Sunday.

Thousands of secondary school girls had flocked to classes on Wednesday after the hardline regime reopened their institutions for the first time since seizing power last August.

But officials ordered the schools shut again just hours into the day, triggering international outrage.

"We call on the leaders of the Islamic Emirate to open girls' schools within one week," activist Halima Nasari read from a statement issued by four women's rights groups at a press conference in Kabul.

"If the girls' schools remain closed even after one week, we will open them ourselves and stage demonstrations throughout the country until our demands are met."

The Taliban should be building more schools for girls in rural areas rather than shutting existing facilities, said the statement, which comes after several women's activists were detained in recent months.

"The people can no longer tolerate such oppression. We do not accept any excuse from the authorities," it said.

On Saturday, about two dozen schoolgirls and women staged a protest in Kabul demanding the reopening of the schools.

"Women, teachers and girls should come out on the streets and protest," said student Zarghuna Ibrahimi, 16, who attended the press conference.

"The international community should support us."

The education ministry has so far not given a clear reason for its policy reversal, but senior Taliban leader Suhail Shaheel told Agence France-Presse (AFP) that some "practical issues" were still to be resolved before reopening the schools.

Separate days at parks

Since storming back to power the Taliban have rolled back two decades of gains made by Afghanistan's women, who have been squeezed out of many government jobs, barred from traveling alone and ordered to dress according to a strict interpretation of the Quran.

The Taliban had promised a softer version of the harsh rule that characterized their first stint in power from 1996 to 2001.

But many restrictions have still crept back, often implemented locally at the whim of regional officials.

Some Afghan women initially resisted the curbs, holding small protests where they demanded the right to education and work.

But the Taliban soon rounded up the ringleaders, holding them incommunicado while denying that they had been detained.

Since their release, most have gone silent.

On Sunday, the Taliban's ministry for the "propagation of virtue and the prevention of vice" ordered that men and women should not visit parks in Kabul on the same days.

Women are now permitted to visit parks on Sunday, Monday and Tuesday, while the remaining days were reserved for men, a ministry notification said.

"It is not the Islamic Emirate's order but our God's order that men and women who are strangers to each other should not gather at one place," Mohammad Yahya Aref, an official at the ministry, told AFP.

"This way women will be able to enjoy their time and freedom. No man will be there to trouble them," he said, adding that religious police were already implementing the order.