NEW DELHI, FEB. 19 -- Afghanistan rejected Pakistan's demand for the formation of an interim government in Kabul before any Soviet troop withdrawal.

"How can an outsider decide the sort of government Afghanistan is to have?" Afghan Ambassador Abdul Samad Azhar asked at a news conference here.

But in Islamabad, Pakistani President Mohammed Zia ul-Haq warned there would be further bloodshed if the demand was not met.

Zia told newspaper editors Moscow's insistence on negotiating a pullout of its 115,000 troops without discussing an interim government is a ploy to avoid blame for a civil war that could follow its withdrawal from Afghanistan.

"So long as a government installed by the Soviet Union is in power, bloodshed will continue," Zia said.

Pakistan last week linked any final settlement of the eight-year-old conflict to the installation of a broad-based interim government in Kabul acceptable to the Pakistan-based Moslem resistance and the more than 3 million war refugees camped along his country's border with Afghanistan.

On March 2, Pakistan and Afghanistan are scheduled to begin their 11th round of indirect negotiations in Geneva aimed at ending the war and allowing a pullout of Soviet troops.