ISLAMABAD, Pakistan (CNN) -- About 35 American activists dressed in pink are expected to take part in a demonstration Friday in Islamabad against U.S. drone strikes that target militants in Pakistan.

The U.S. protesters, from the anti-war group Code Pink, are visiting Pakistan to make contact with people affected by the drone strikes and draw the attention of the American public to the situation in areas where the attacks take place.

"We are here to say, on behalf of those Americans with a conscience, that we apologize to the people of Pakistan for the killing and suffering" caused by the drones, Medea Benjamin, one of the founders of Code Pink, said at a news conference Thursday in Islamabad.

Organized in conjunction with a British advocacy group, the rally Friday is scheduled to take place in one of the Pakistani capital's busiest market places. The protesters say they plan to wear bright pink clothes, carry banners and recite anti-drone chants.

The drone strike program in Pakistan has long been controversial, with conflicting reports on its impact from the U.S. government, Pakistani officials and independent organizations.

American officials insist that the choice and execution of the strikes -- begun under former President George W. Bush and ramped up under President Barack Obama -- meet strict standards and that cases of civilian deaths or injuries are extremely rare.

But a study released last month by Stanford Law School and New York University's School of Law said the drone attacks had killed far more people than the United States acknowledges, traumatized innocent residents and been largely ineffective. Civilians account for a significant portion of those killed, the study said.

The drone program is deeply unpopular in Pakistan, where the national parliament voted in April to end any authorization for it.

Code Pink's demonstration Friday in Islamabad is the precursor to a bigger, more ambitious protest over drone strikes in which the group plans to participate over the weekend.

The activists say they hope to join cricket-star-turned-politician Imran Khan and his party, Pakistan Tehreek-e-Insaf, in a march to South Waziristan, part of Pakistan's ungoverned tribal region along the Afghanistan border where drone strikes are frequent.

But the activists say they are unsure if the Pakistani government will allow them to take part in the march to the restive region.

The neighboring district, North Waziristan, is widely believed to be the headquarters of the Haqqani network -- a militant group Washington has long accused of fueling some of the deadliest attacks against NATO troops in Afghanistan.

If the authorities prevent them from participating in the march to South Waziristan, the Code Pink activists say they will invite people from the area affected by the drone strikes to join them in a large gathering in Islamabad.

They say they are also considering the possibility of a hunger strike outside the U.S. Embassy in the capital.

Code Pink says on its website that the broader goal of its Pakistan trip is to "stop the drone strikes and get compensation for the families of civilians killed by the strikes." It has held meetings in Islamabad this week with victims of the strikes and U.S. officials.

The women-led organization became known for antiwar demonstrations in Washington during the U.S. buildup in Iraq. The group has held protests over a range of different international issues.

Code Pink has regularly disrupted high-profile congressional hearings dealing with war and national defense issues, as well as interrupting speeches by foreign officials like Prime Minister Benjamin Netanyahu of Israel.

Among the activists with the Code Pink delegation in Pakistan at the moment is Ann Wright, a former U.S. Army colonel and State Department official who quit her post to protest the U.S. invasion of Iraq.

In an appearance this week on the Pakistani television station Geo TV, Wright said that U.S. drone strikes are a violation of Pakistan's sovereignty and are fueling anti-American sentiment in the region.

When the Pakistani television host asked Wright to respond to accusations that she was a radical activist, she said jokingly, "I'm a radical peace activist."

CNN's Shaan Khan reported from Islamabad, and Jethro Mullen from Hong Kong. CNN's Reza Sayah contributed to this report.