Proclaiming allegiance to a broad new opposition front, Iraqi Kurds are seeking to resume their uprising against the Baghdad government after more than six years of relative submission, according to reliable reports from the area.

The unrest, in several areas of northern Iraq, reflects in part a weakening of Iraqi Army control because of the need to assign forces to other regions for the 15-month-old war with Iran. The reports, reaching here from front leaders, say the front has been encouraged by fresh military and financial aid from Syria and Iran along with better organization by the still-shaky coalition, which groups Kurds, dissident Baathists, breakaway Iraqi Army officers and Shiite Moslem religious leaders.

A European diplomatic source, confirming the tenor of the reports, said Iraqi Army control diminished sharply beginning this fall in northern Iraqi Kurdistan, becoming limited to the region's major towns and roads at night. Most fighting occurs during ambushes on Iraqi Army patrols by newly rearmed Kurdish Pesh Merga rebel forces, although winter weather in the mountainous northern region has forced a slowdown in recent weeks, a front leader reported.

The diplomat said it is too early to predict whether the renewed uprising will evolve into another major problem for President Saddam Hussein, who has encountered increasing difficulty in the unexpectedly long war with Iran. In any case, it already is an unwelcome harassment at a time when Iraqi forces have suffered several reversals in the fight against Iran, they said.

The opposition grouping has named itself the Iraqi Front of Revolutionary, Islamic and National Forces. It was formed last July in Damascus with the proclaimed goal of toppling Saddam Hussein and replacing him with a government pledged to democratic freedoms, including local autonomy for Iraqi Kurds.

The front's emergence appears to mark the most successful attempt so far to end the long history of disputes between various Iraqi rebel groups based in Damascus but unable to join forces effectively against their common enemy. Despite a joint charter and close cooperation on the ground, however, political differences still trouble the front's disparate groups, which range from secular Baathists to fundamentalist Shiite mullahs.

"There are problems; yes, there are problems," a front leader acknowledged in an interview here.

The grouping nevertheless establishes, for the first time since the Kurdish uprising was crushed in March 1975, effective links between major Kurdish rebel groups and Saddam Hussein's political opponents with access to Syrian or Iranian backing. In addition, it has resulted in agreement on an overall military commander to coordinate operations and supplies from Iran and Syria, he said.

Participation of the commander, Gen. Hassan Mustafa Naqib, was regarded as a crucial asset, the front leader said. The Iraqi officer was part of the July 1958 revolution that overthrew the Iraqi monarchy and had been assistant chief of staff in Baghdad and Iraqi ambassador to Spain and Sweden before becoming an exile in 1978. He was said to be running a command center near the Iranian border.

The most effective aid comes from Syria, the front official said, because Iranian officials feel the front is too distant from their own Islamic-based revolution despite the participation of Iraqi Shiite leaders. At the same time, Iranian Army officers provide some arms, allow border crossings and allow a rebel broadcast station to beam antigovernment programs from Iranian soil, he added.

Groups in the front, the official said, include:

The Kurdish Democratic Party led by Massoud Barzani, son of the legendary Mullah Mustafa Barzani who led the Pesh Merga until the 1975 debacle and died in Virginia in March 1979. The younger Barzani's guerrillas make up the bulk of the front's fighting forces, said to total about 5,000.

Opposition segments of the Iraqi Baath Party, led by Bakr Yassin and backed by Syria as part of the perennial struggle between the Syrian and Iraqi wings of the Arab Baath Socialist Party.

The Kurdish Socialist Party, a smaller group than Barzani's, led by Rasoul Mamendeh.

Exiled Shiite Moslem chiefs in touch with Iranian mullahs and accused by Saddam Hussein's government of attempting to foment a Khomeini-style revolution in Iraq.

Iraqi Shiites, a thin majority of the country's 12 million inhabitants, represent a potentially explosive opposition to Saddam Hussein's Sunni-run government. But the front leadership proclaims religious freedom as part of its platform and its envoy here insisted that it has no fundamentalist goals.

In addition, he said, the front has the support of several Iraqi Army officers and coordinates closely with the Iraqi Communist Party. On the other hand, he acknowledged, it remains locked in dispute with the Syrian-backed Kurdish group led by Jalal Talabani and has drawn the wrath of the chief Iranian Kurdish leader, Abdol-Rahman Ghasemlu, because the unrest in Iraq troubled clandestine Iraqi supply lines to Ghasemlu's anti-Tehran Kurdish rebels last fall.

The front's Iraqi Kurdish guerrillas have mounted a number of attacks in a stretch of rugged terrain from Rawanduz, about 25 miles from the Iranian border, through Has Umran and Zakhu to Amadiyah near the Turkish border, the front official said. More than 3,000 guerrillas, mainly Pesh Merga Kurds, are under arms in the area, 270 miles north of Baghdad, he said.

"The [Iraqi] Army is not very numerous there any more," he added. "Why? Because they are involved in the war with Iran; that is why our men are able to make continuous operations."

A second area of unrest lies around Halabjah, about 15 miles west of the Iranian border and 40 miles southeast of Sulaymaniyah, the envoy said. Around 2,000 guerrillas operate in this region and captured several tanks from the Iraqi Army in a clash last Sunday, he added.