Naypyidaw, Myanmar: At least 160 people have died in three months of clashes between the military and ethnic armed groups in Myanmar's Shan state, a senior army official said Tuesday, amid efforts to revive flagging peace talks.

More than 20,000 people have been displaced since fighting between the army and several armed ethnic groups erupted near the border with China in late November.

The unrest has rippled across the northern state of Shan and into neighbouring Kachin, hampering a push by Aung San Suu Kyi's government to end the country's decades-long borderland conflicts.

Military offensives that had been rumbling since mid-2016 intensified after several armed groups, together known as the Northern Alliance, launched a major attack in northern Shan. The army responded with heavy artillery and air strikes.

Experts say the fighting in the frontier areas is at its most intense since the 1980s.

That has prompted the UN to warn of a humanitarian crisis building in conflict areas, particularly in Kachin where some 100,000 people have been displaced since 2011.

Giving the army's first comprehensive toll from the clashes, the chief of the general staff said 74 soldiers, 15 police, 13 government militia fighters and 13 civilians have been killed.

"We have 45 dead bodies of enemies and arrested four," General Mya Tun Oo told reporters in the capital, Naypyidaw, speculating hundreds more rebels may have died in the violence. 

The toll comes as Myanmar's government prepares for a second round of peace talks, currently slated for March. The negotiations have repeatedly been pushed back because of political deadlock with armed groups. 

Suu Kyi wants to broaden a ceasefire signed with some of Myanmar's myriad ethnic insurgent groups in 2015 and known as the NCA.

The most recent negotiations were delayed after the powerful China-backed United Wa State Army (UWSA) militia held its own summit with non-signatories to the deal.

After that meeting attendees signed a statement rejecting the NCA.

Instead they called for an immediate halt to military offensives in ethnic areas and for the UN and China to be involved in the new talks.

They have also backed the UWSA's calls for Myanmar's major ethnic groups to be granted more control over their territories and resources. 

"The NCA is not fair," a spokesman for the powerful Kachin Independence Army (KIA), which attended the talks, told AFP. 

"The army's vision is not what the ethnic groups want." 

The KIA is among several groups which are set to hold talks with Suu Kyi this week in the capital to try to break the deadlock.

IHS Jane security analyst Tony Davis said the recent fighting has "lent credibility" to the UWSA, also known as the Wa, in peace negotiations.

"The Wa-backed Northern Alliance... has effectively dismissed the government's NCA-centred peace process, which despite Western advice and lavish funding has never gained any real traction," he said.