U.N. officials and diplomats say the Sudanese government has become increasingly confrontational toward the United Nations and the West over the joint U.N.-African Union mission to Darfur (UNAMID), which Khartoum wants shut.

U.N. peacekeeping deputy chief Edmond Mulet told the 15-member Security Council that there has been negligible progress in peace efforts for Darfur, adding there was a worrying rise in attacks on UNAMID.

U.N. chief Ban Ki-moon’s latest progress report on the force said there were 60 “incidents and hostile attacks against UNAMID” in the three months to May 15, compared with 46 in the previous quarter.

Mulet noted that the second phase of the government’s “Decisive Summer” military campaign to end armed rebellions has caused a new wave of displacement across Darfur. He said humanitarian organizations estimated at least 78,000 newly displaced this year, while the U.N. has unverified reports of 130,000 more.

Sudan’s Deputy U.N. Ambassador Hassan Hamid Hassan told the council that the violence and displacements were mainly due to tribal clashes and attacks by rebels, not government forces. He added that the government’s operations have brought stability to Darfur.

UNAMID has faced allegations by Western powers it has not done enough to protect civilians and withheld information on the scale of violence against civilians and peacekeepers by the Sudanese army and allied militias. U.N. officials say UNAMID has been working to improve its performance.

UNAMID acting chief Abiodun Bashua told a small group of reporters that the force is currently on such a high-level of alert that any attack or ambush is met with a robust response. He cited several recent incidents in which UNAMID troops from Tanzania and Pakistan killed a number of attackers.

But he complained that Sudanese authorities continue denials of access even though UNAMID’s mandate allows the force to go anywhere in Darfur without permission. Asked why UNAMID did not simply disregard government attempts to stop it, he said:

“Robust doesn’t mean committing suicide.”

In addition to a 12-month extension of the force’s mandate, Ban has recommended some reconfigurations and a gradual drawdown based on the ability of the government and armed groups to make progress on peace. He did not recommend withdrawing the force as demanded by Khartoum.