Iraq has deported 5,700 Iranians over the past few days and plans to expel as many as 20,000 in all within "one or two weeks," a member of the ruling Revolutionary Command Council said today.

Council member Naim Hadded said in an interview at the ruling Baath Party's headquarters here that "we have deported Iranians of Persian descent . . . who do not have Iraqi nationality."

But observers suggested that in some cases, Iraqi citizens whose grandparents were Iranian nationals may have been deported as well.

The expulsions follow report of a series of border skirmishes between Iran and Iraq and a rising level of denunciation and conflicting charges. Iran, for example, claimed today that Iraq already had expelled more than 25,000 Iranians.

This current clash between the two countries, whose thousands of years of common history are marked with more bad blood than good neighborliness, began April 1 with what Iraq claims was an Iranian assassination attempt on Deputy Premier Tariq Aziz. Four days later, there was a grenade attack during a funeral procession for the first attempt's victims.

Eyewitnesses report seeing as many as 500 Iranians confined in a single bus depot in Baghdad that is being used as one of many gathering points before they were trucked to a central collecting area and transported to the Iranian border.

Even toothless old men or babes in arms were allowed only what they or their families could carry in a blanket,according to the eyewitnesses.

Iraq's authoritarian regime has deported Iranians in the past. It forced 60,000 to leave the country in late 1974, only months before the two countries, under U.N. mediation, reached an agreement ending Iranian aid to a crippling Iraqi Kurdish rebellion.

At that time it was shah Mohammad Reza Pahlavi at the height of his powers who dictated terms to an exhausted Iraqi regime.

Then, as Haddad said today, "we signed in very different circumstances."

Today Haddad warned the Iranian armed forces that "we will give them a lesson they will never forget" if serious fighting breaks out.He also ran through a list of now-familiar demands on a weakened revolutionary Iran.

Iraq is demanding Iran to give up three "Arab islands" near the strategic Strait of Hormuz that the deposed shah seized in 1971. The islands were taken from the United Arab Emirates and Iraq says they should be returned to Arab control.

Similarly, Iraq wants to declare all the Shatt-al-Arab estuary -- which leads to the Persian Gulf -- a purely Iraqi waterway, as was the case before the 1975 settlement in which Iraq gave half of it to Iran.

Haddad's tone was disparaging. "Expansionist Persian imperialists and fascists," he said, were refusing to allow the various Iranian national minorities -- including the Baluchis in southeastern Iran, the Turkomans in the northeast, and the Kurds in the west -- to enjoy their national rights.

Formost of these minorities, he made clear, were the Arab inhabitants of the oil-rich Iranian province of Khuzestan, which he kept referring to as Arabestan, the name Iraqi officials used before Baghdad formally dropped its claims to the area as part of the 1975 settlement.

He predicted that Iran "will be shattered" after Ayatollah Ruhollah Khomeini dies -- and perhaps even before -- because of what he saw as a misguided policy toward the national minorities that would lead to their "indenpendence," although they are now demanding only autonomy.

Iraq was providing "all forms" of aid -- presumably including money, arms and ammunition -- to these minorities, but only to help them in their efforts to achieve autonomy, he said.

He insisted Iraq wanted "coexistence based on mutual respect for sovereignty and noninterference in each other's affairs," but indicated that he thought shortsighted Iranian policies would make the minorities demand independence.

Haddad denied that an independent Kurdestan in Iran would provide a potentially dangerous precedent for Iraq's own Kurds. They have fought a series of losing wars against Baghdad and now live in very limited autonomy.

Apparently bent on exuding confidence, Haddad consistently turned aside questions about whether Iraq had followed Iran in putting its own forces on a special alert at the border in recent days.

Iranian news media offered a wealth of purported detail -- artillery exchanges, Iraq helicopter gunship forays into Iran, fixed-wing aircraft on war missions.

But Haddad dismissed these, noting that "the Iranian Army is not even able to control the events inside Iran" and added that "the Iranians do not derserve a special alert."

He conceded that "continuous clashes" had been going on along the border, but suggested that this had become a nearly everyday occurrence in past months. b

Al Thawra, the official Baath daily, dismissed Tehran's claims of border fighting as a "distraction," designed to divet "the attention of the Iranian people from their basic demands" over unemployment, political unrest among national minorities, and shortages of goods.