There has been anger and dismay in South Asia following the start of the US-led war on Iraq.
Protesters in Delhi burn an effigy of President Bush
Pakistan said it deplored Thursday morning's attack.
India said the attacks were unjustified.
There have been a number of anti-American demonstrations in the region.
Residents of the Afghan capital, Kabul, said the attacks marked a dark day for Muslims.
"Pakistan deplores the initiation of military action against Iraq," Foreign Minister Mian Mehmood Kasuri said on Thursday.
We want the government to give us permission to go to Iraq to fight against the US forces
He also said Pakistan regretted that Saddam Hussein had not considered all options to save the Iraqi people from death and destruction.
As a member of the UN Security Council, Pakistan had come under pressure from the United States to support a proposed second UN resolution supporting military action against Iraq. The resolution was eventually abandoned.
Anger on the streets of Pakistan was reflected in a number of relatively small demonstrations.
"Saddam Hussein is a hero of Muslims," a protester cried at a rally in the north-western city of Peshawar, AFP reports.
US missions throughout the region are on alert
"We want the government to give us permission to go to Iraq to fight against the US forces," another protester told hundreds of supporters.
Supporters of the Islamic Jamaat-i-Islami party assembled in the eastern city of Lahore, chanting "Bush is a dog," and "Save Iraqi children," AFP reports.
"America has signed its own death warrant," Islamist leader Maulana Fazlur Rehman said.
Further rallies are due to be held on Thursday.
The Indian Government also made plain its opposition to the US attacks.
"The military action that began today lacks justification," Indian Foreign Ministry Spokesman Navtej Sarna said.
Bush and Blair have become war criminals
Sri Lanka opposition spokesman
It was a matter of grave concern that military action was carried out despite differences between members of the UN Security Council over the issue, he said.
Mr Sarna added that the Iraqi people should not be subjected to further hardships from an extended military operation and that India would be ready to play its part in all efforts to deliver humanitarian relief.
He was speaking after Prime Minister Atal Behari Vajpayee called a cabinet meeting to discuss the war.
India's most senior Muslim cleric denounced the attacks.
"Indian Muslims consider the American attack on Iraq as an attack on Islam and humanity," Imam Bukhari said, AFP reports.
"America, by attacking Iraq, has proved that it does not care for international laws, UN charters or international public opinion."
Nearly 200 women took part in an anti-war demonstration in the Indian capital Delhi. The protestors, under the banner of the World March of Women, gathered outside an office of the US embassy in Delhi.
UN is 'nothing'
In the Afghan capital, Kabul, people expressed their anger at the US and the United Nations.
"Today is a dark day for Muslims," 50-year-old Sher Aga told the Associated Press news agency. "I hope the aggressors will be buried."
"The United Nations is nothing anymore."
Former soldier Sayed Mafouz Durani warned: "Today they're attacking Iraq. Tomorrow they'll be attacking another Muslim country."
The message is clear in this poster in Multan, Pakistan
Several anti-war demonstrations have taken place in the Bangladesh capital, Dhaka.
Children formed a human chain in central Dhaka condemning the attack and chanting anti-war slogans.
The Bangladesh Government said it was unfortunate that a peaceful resolution could not have been found to the Iraq isse.
The Sri Lankan Government expressed grave concern at the situation. A statement said it was due to the lack of full Iraqi compliance of UN resolutions that Iraq's weapons of mass destruction could not be eliminated through peaceful means.
But Sri Lanka's biggest opposition party, the People's Alliance described the US and British leaders as criminals.
"Bush and Blair have become war criminals by their action of going to war without United Nations approval," People's Alliance spokesman Tissa Vitharana said.
In Nepal, security has been enhanced for western diplomats.