A civilian politician widely believed to be a pro-Moscow Communist was appointed yesterday, to head the new government in Afghanistan, four days after a bloody military coup toppled President Mohammed Daduo.

Radio Kabul, monitered here in Pakistan's capital said that Nur Mohammed Taraki, a former leader of the Moscow-oriented Kharo (masses) party was declared "founder of the revolution," President of Afghanistan, and prime minister of the new government.

The Soviet Union announced its recognition of the new government, Radio Kabul said. There has been no confirmation from Soviet sources.

Diplomatic sources in Washington said Taraki was named chairman of a United Communist Party, when the various Communist factions merged in 1977. The sources said Taraki, who is about 61, once served in the Afghanistan Embassy in Washington and later worked as a translator in the U.S. Embassy in Kabul.

[The sources said that while the Afghani Communists are thought to lean toward Moscow their nationalism may be a more significant factor].

[Noting that Taraki has taken both the position of chief of state and head of the cabinet, the sources said it is unlikely he will be a figurehead.]

Were a Communist government to be established in Afghanistan, observers say, it would have major impact in other South Asian states and on nations along the Persian Gulf and Indian Ocean.

Such a government would be expected to be an encouragement to separatist movements in neighboring Pakistan. Western diplomats in Islamabad said they regard the situation with what one described as "cautious concern-but very real concern, indeed."

Immediately after the coup the rebels said that their new government's foreign policy would be based on "strict nonalignment, peaceful coexistence and the tenets of Islam."

The position of Air Force Col. Dagawar Abdul Khadir, whom foreign sources initially described as leader of the military council that seized power, is not clear following yesterday's appoinment of a civillian leader.

Radio Kabul said that Taraki, who has not held office in any previous Afghan government, was a "revolutionary personality." He apparently heads a Cabinet of civilian and military officials, answerable to what was called a "Democratic Republican Revolutionary Council.

The new Cabinet reportedly met in Kabul yesterday morning, and issued a decree that martial law would continue to operate in the impoverised, land-locked country "until the revolutionary council decides it is not longer needed."

Other reports from Kabul said that the city was calm, shops were open and people were on the streets. Tanks and armored cars were still patrolling however, and the road between Kabul and the Pakistan border was lined with troops and anti aircraft guns.

The northeastern town of Jalabad was still controlled by troops loyal to the former president until yesterday, Pakistani sources said, but a major thrust by rebel troops yesterday morning reportedly disarmed the garrison and killed the commanding general.

The coup, which began Thursday afternoon, appears to have been even more violent than was first reported. According to some eyewitness reports relayed by embassies in Kabul, as many as 30 members of President Daoud's family were machine-gunned to death in the compound of the presidential palace. Some reports said that Daoud, who was 69, was forced to watch some of his closest relatives being slain while being asked to sign an oath of loyalty to the new government. He refused and was reportedly shot dead at point blank range by an officer with a pistol.