Brussels has invited some 85 governments and non-governmental agencies to raise funds for humanitarian aid, limited reconstruction and de-mining.

* Brussels conference to focus on emergency aid funds

* EU hosts hope Iran, Turkey, Russia send top officials

By Robin Emmott and Gabriela Baczynska

BRUSSELS, April 23 (Reuters) - Governments will seek more than $6 billion in aid for Syria at a two-day donor conference from Tuesday, which the European Union hopes will also offer Russia, Turkey and Iran a chance to renew peace efforts.

As the conflict enters its eighth devastating year, Brussels has invited some 85 governments and non-governmental agencies to raise funds for humanitarian aid, limited reconstruction and de-mining of shattered cities.

Syrian army targets south Damascus insurgent enclave

"Funding the aid response is critical," said Robert Beer at aid agency CARE International. "But funding is only part of the picture - the systematic and deliberate blocking of aid inside Syria must end, and aid workers must be granted unimpeded access to civilians," he said in a statement.

This, the third annual conference after London in 2016 and then in Brussels last year, could help return some electricity and water to cities heavily damaged in the West's campaign to push out Islamic militants.

But the majority is likely to go to help the refugees outside Syria and the millions displaced within, including some 160,000 people who fled a bombing campaign by Syrian ally Russia in eastern Ghouta near Damascus over the past six weeks.

The $6-billion target is similar to the amount raised last year, but officials say they want to go beyond that level now.

Rebuilding destroyed cities such as Aleppo is likely to take billions more dollars, however, and cannot start until powers involved in the proxy war back a peaceful transition away from the rule of Syrian President Bashar al-Assad, the EU says.

Some of the biggest aid donors include the European Union, the United States, Norway and Japan.

Governments are also expected to send senior ministers, with Turkey's Deputy Prime Minister Recep Akdag confirmed and, possibly, Iran's Foreign Minister Mohammad Javad Zarif due, EU officials said.

Russia's Foreign Minister Sergei Lavrov has been invited, but it is not clear he will attend. The United Nations special envoy for Syria, Staffan de Mistura, who met Lavrov in Moscow on April 20, is also expected in Brussels.

Last year's absence of top-level officials from Russia, Turkey and the United States, as well as a chemical attack in Syria, overshadowed the conference's efforts to help end the conflict between anti-Assad rebels, Islamist militants, Syrian troops and foreign forces.

This time, the EU's top diplomat Federica Mogherini is appealing to the trio of Iran, Russia and Turkey - the key powers with direct military involvement in the war - to support a lasting ceasefire to allow aid access and medical evacuations.

Mogherini wrote to the three last February to demand a 30-day humanitarian ceasefire. That has not seen a response as yet, said an EU official involved in Syria policy.

(Writing by Robin Emmott, Editing by William Maclean)

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