* U.N. anti-drugs chief says Iranian opium seizures "impressive"
* But will raise issue of death penalty with Iranian officials
VIENNA, March 11 (Reuters) - The U.N. anti-drugs chief has praised Iran's fight against narcotics trafficking despite what human rights groups describe as a surge in executions in the country, many of people convicted of drug-related offences.
Yury Fedotov, executive director of the U.N. Office on Drugs and Crime (UNODC), said the Vienna-based agency opposes the death penalty and he planned to raise the issue again with Iranian officials later this week.
"But on the other side, Iran takes a very active role to fight against illicit drugs," he told reporters before a international meeting in Vienna on March 13-14 on global efforts to combat narcotics.
In 2012, Iran seized 388 tonnes of opium, the equivalent of 72 percent of all such seizures around the world.
"It is very impressive," Fedotov said.
Because of a large number of executions, some countries - including Britain and Denmark - have in recent years stopped providing funding for UNODC drug control programmes in Iran, diplomats say.
But Fedotov made clear the UNODC was not considering halting support for Iran.
"I don't believe that the international community would welcome this because it would mean, as a possible reaction from Iran, that all these huge quantities of drugs, which are now being seized by Iranians, would flow freely to Europe," he said.
Iran shares a long border with Afghanistan, which supplies about 90 percent of the world's opium, from which heroin is made. Iran says it has lost many security personnel in skirmishes with drug traffickers in volatile regions bordering also Pakistan.
On Feb. 21, the United Nations said at least 80 people and perhaps as many as 95 had been executed in Iran so far this year.
Possession or transport of drugs, "even in relatively small amounts" of less than 500 grams, frequently leads to execution, Roya Boroumand, director of the U.S.-based Abdorrahman Boroumand Foundation that tracks executions in Iran, said at the time.
Amnesty International said in mid-January that Iran had carried out 40 executions since the beginning of the year and that most of those executed had been convicted of alleged drug-related offences. (Reporting by Fredrik Dahl; Editing by Angus MacSwan)