* EU sanctions target Syrian industry for first time
* Western experts say EU approach needs more bite
* Human rights group says four killed on Saturday
* Russia says sanctions 'will lead to no good'
SOPOT, Poland, Sept 3 (Reuters) - The European Union imposed a ban on purchases of Syrian oil on Saturday and warned of further steps unless President Bashar al-Assad's government ends its five-month crackdown on dissent.
The sanctions mark the first time Europe has targeted Syrian industry in a bid to stem the violence, which claimed another four lives on Saturday and has so far killed more than 2,200 people, according to the United Nations.
The Syrian Observatory for Human Rights said three people were killed after security forces went into the village of Haysh near the second city Aleppo looking for attorney general Adnan Bakkour, who resigned last month in a video posted on YouTube.
Bakkour's resignation, if confirmed, would be the first high-profile defection during the recent uprising.
The authorities instead say Bakkour was kidnapped while travelling to work on an agricultural road to the Justice Palace in Hama.
The Observatory also said another civilian had been killed on Saturday during a morning raid in Syria's third-largest city, Homs, and that the death toll from attacks on protesters on Friday had risen to 21 from 14.
While most of Syria's oil exports have gone to Europe, the EU sanctions agreed on Saturday do not go as far as an investment ban imposed by the United States last month, and analysts say they may have only a limited impact on Assad's access to funds.
EU governments are expected to have talks on further sanctions, but industry experts have said the 27-member bloc will have to overcome reluctance among some capitals, given that European firms like the Anglo-Dutch Royal Dutch Shell (RDSa.L) and France's Total are significant investors in Syria.
At informal EU talks in the Polish resort of Sopot, French Foreign Minister Alain Juppe and his British counterpart William Hague said more oil sanctions could be needed, but did not say what these might entail.
Hague said the ban covered around 95 percent of Syrian exports and 25 percent of the revenue to the Syrian government.
"If Bashar al-Assad is not listening and if there is no change in the regime, the sanctions will have to be intensified," Juppe told reporters.
Hague declined to make clear when asked in an interview whether Britain would back extending EU sanctions to a ban on investment by EU firms in Syria, but he called the new EU response a serious one.
"We would ask other countries in the world to join us in making it," he told Reuters.
RESISTANCE AT U.N.
Hague and Juppe both said the EU would continue to press for a tougher response at the United Nations, where some global powers, including Russia and China, have resisted a push led by the United States and Europe for a U.N. Security Council resolution laying out more measures.
"We're trying to convince India, Brazil and South Africa ... and to convince the Russians not to impose their veto," Juppe said.
He said it was necessary to accelerate a change of regime in Syria and to help the opposition to organise.
As well as banning oil imports, the new EU sanctions target Syria's Real Estate Bank, which provides mortgage finance, as well as Mada Transport and the Cham Investment Group, two arms of a Syrian investment firm which the EU says provides funds to Assad's government.
Four Syrian businessmen were also added to a list of people affected by EU asset freezes and travel bans.
However, underscoring the EU divisions that have slowed the implementation of economic measures against Assad, Italy won an exemption on oil contracts agreed before the new sanctions round, which can be fulfilled until Nov. 15.
Other ministers, including Juppe and Finnish Foreign Minister Erkki Tuomioja, said it would have been better to implement the ban faster.
"I feel (it) is too late," Tuomioja told reporters. "If we are serious, we should take any steps we take immediately."
Hague acknowledged that Syria could opt to export its oil elsewhere, but said transportation and logistics issues made this difficult.
Russian Foreign Minister Sergei Lavrov condemned the EU European sanctions.
"We have always said that unilateral sanctions will lead to nothing good. This ruins the partnership approach to any crisis," he told reporters on the sidelines of a summit of ex-Soviet states in the Tajik capital Dushanbe.
Meanwhile, the head of the International Committee of the Red Cross began a visit to Syria to discuss gaining access for the first time to its prisons -- where thousands of activists and other civilians arrested in pro-democracy protests are believed to be held. (Addtional reporting by Julien Toyer in Sopot, Denis Dyomkin in Dushanbe, Emma Thomasson; in Zurich and Mariam Karouny in Beirut; Editing by Mike Nesbit)