By Emma Graham-Harrison
KABUL (Reuters) - Iran's defense minister made a landmark visit to Afghanistan on Saturday to bolster ties as Kabul prepares to assume security control from NATO-led forces and Washington seeks to wind down its almost decade-old tenure.
Majority Shi'ite Iran and majority Sunni Afghanistan share a long border and history, and Western powers have alleged that Tehran's involvement included supporting the Taliban insurgency to compete with U.S. influence. Iran denies that charge.
"The Islamic Republic of Iran considers Afghanistan's security as its own security, has put a lot of effort toward stability in Afghanistan and will continue to help in this regard," Iranian state broadcaster IRIB quoted Defense Minister Ahmad Vahidi as saying.
Vahidi's visit, during which he met Afghan counterpart Abdul Rahim Wardak, was the first by an Iranian defense minister in 92 years, according to IRIB.
"On this trip I hope to witness the expansion of defense ties between the two countries," Vahidi said.
Wardak's ministry said the two discussed challenges such as terrorism, drugs and arms smuggling, crime and border security.
"Both Islamic countries emphasized that according to their common faith, culture, language, historical and social values, they will respect each other's independence, territorial integrity and national sovereignty," it said in a statement.
In coming months, foreign troops will hand security control in parts of Afghanistan to the national police and army, launching a years-long process that Western nations and Kabul see giving Afghans all security control by the end of 2014.
President Barack Obama is also expected to announce soon how many troops he plans to withdraw starting in July, as part of a commitment to begin reducing the U.S. military presence and meeting the 2014 security transition goal.
The United States is on the verge of announcing a "substantial" drawdown, Senate Majority Leader Harry Reid said on Friday. There currently are about 100,000 U.S. troops, up from about 34,000 when Obama took office in 2009.
While Iran will be happy to see the start of a drawdown in U.S. troops, it is concerned about drug smuggling from Afghanistan -- the world's biggest exporter of opiates -- and the presence of al Qaeda in the region.
U.S. military officers have long alleged Iranian support for the Taliban. Britain said this year that NATO had identified a cache of weapons seized in Afghanistan as coming from Iran and destined for Taliban insurgents.
Afghan President Hamid Karzai has acknowledged that his office receives "bags of money" from Iran, which he says is a form of aid that helps cover presidential palace expenses.
(Additional reporting by Ramin Mostafavi in Tehran; Writing by Robin Pomeroy; Editing by Dan Williams)