"We appeal to the kidnappers of Malik Mohamed Javed to release him immediately," said Pakistan's Information Minister Sheikh Rashid.
Rashid said one of the kidnappers had contacted Pakistan's charge d'affaires in Iraq by telephone on Sunday and told him that Javed, who has no diplomatic status, was in their custody.
Pakistan's Foreign Office spokesman Jalil Abbas Jilani said that his office in Islamabad has contacted the Iraqi ambassador in Pakistan concerning embassy official's abduction.
Jilani said that the area where the diplomat had gone for prayers was put under curfew by Iraqi authorities and it was felt that he might have been stuck up somewhere.
When asked whether US authorities have been approached, he said, "We have contacted only Iraqi government." He replied in the negative when asked if any militant group has contacted the family or the government regarding the diplomat, but added that the Iraqi government has assured of its full co-operation.
Amid continuing violence in which at least 10 people died, Iraqi authorities said they had arrested a nephew of toppled Iraqi president Saddam Hussein suspected of playing a major part in financing the insurgency.
Officials said they recently detained Ibrahim Sabawi - son of Sabawi Ibrahim al-Tikriti, a half brother of Saddam who is also being held in custody - for allegedly bankrolling rebels, a government statement said.
He was captured near Baghdad, the statement said, without giving further details.