JERUSALEM, April 19 (Reuters) - Israeli police refused to let the U.N.'s peace envoy to the Middle East, other diplomats and a crowd of Palestinians pass through a barricade to attend a pre-Easter ritual in the Jerusalem church that Christians revere as the burial site of Jesus, the U.N. official said on Saturday.

The incident, following two days of violence at a separate holy site known as a flashpoint for Jews and Muslims, underscored rising tensions in the politically charged city ahead of Pope Francis's Holy Land visit next month.

Israel dismissed the U.N. complaint, calling it an attempt to inflate a micro-incident and saying police at the barricade keep people back as a crowd-control measure while there was no reported violence among the tens of thousands of Christians who thronged to the Holy Sepulcher Church in Jerusalem's old walled city to witness the Holy Fire ritual.

Holy Fire is a traditional Orthodox Christian ceremony at which worshippers believe a miraculous fire appears at the site identified as Jesus's tomb every year on the day before Easter.

Robert Serry, the United Nation's peace envoy to the Middle East, said in a statement Israeli security officers had stopped a group of Palestinian worshippers and diplomats in a procession near the church, claiming they had orders to that effect.

Serry added in separate remarks to Reuters he had waited with Italian, Norwegian and Dutch diplomats for up to a half hour, crushed by a crowd against a barricade, while Israeli officers ignored his appeals to speak with a superior.

It became really dangerous because there was a big crowd and I was pushed against a metal fence the police put up there, the crowd tried to push really hard, Serry said, adding they might have been trampled had police not finally let them pass.

I don't understand why this happened, he added. I'm not saying I felt my life was in imminent danger, but this wasn't something you associate with a peaceful procession for Easter.

PROBLEM OF JUDGMENT

Terry Balata, a Palestinian witness, said she heard the Israeli officer tell Serry, who was with about 30 other diplomats and worshippers, so what? when he identified himself as U.N. Secretary General Ban Ki-moon's envoy to the region.

Charging unacceptable behavior from the Israeli security authorities, Serry demanded in his statement that all parties respect the right of religious freedom.

An Israeli Foreign Ministry spokesman denied Serry's charges and accused him of displaying a serious problem of judgment as there was no reported violence during the prayers and a customary torch-lit Holy Fire ritual held at the church.

Spokesman Yigal Palmor acknowledged though that police took steps to limit the crowd packed into the church and narrow streets outside it. If there was any pushing and shoving I would say it was a micro-incident, Palmor said.

In a statement, the ministry criticized Serry's charges as an odd communique, adding that Christian officials had thanked Israeli police for their handling of the event.

Had any harm come to the pilgrims due to uncontrolled crowd movements, Mr. Serry would have been prompt to cast responsibility on the same police which he now condemns for doing its job properly, the Israeli statement added.

Israeli police did not immediately comment on the incident, which came as they grappled with tensions elsewhere in the old city where Jews celebrated a week-long Passover festival at the same time as Christians prepared for Easter.

Earlier this week, police confronted Muslim protesters throwing stones near the al-Aqsa Mosque as Jews visited the surrounding area, which Judaism reveres as the place where biblical temples once stood.

Pope Francis plans to visit Jerusalem and holy sites in the occupied West Bank such as Bethlehem when he makes his first Holy Land sojourn as pontiff late in May.

The increased tension in Jerusalem also coincided with a crisis in U.S.-brokered peace talks, at risk of collapsing unless Israelis and Palestinians agree to extend negotiations to resolve their conflict past an April 29 deadline. (Writing by Allyn Fisher-Ilan; Editing by Tom Heneghan and Tom Brown)