* Core profit misses forecast, revenue beats
* Political and trade tensions cloud outlook
* Shares fall nearly 12 percent at one point
* New ship orders on hold for 12 months (Adds chart, details, background)
COPENHAGEN, May 17 (Reuters) - A.P. Moller-Maersk missed first-quarter profit expectations on Thursday and warned that political and trade tensions clouded the outlook, sending shares in the world's biggest container shipper sharply lower.
Earnings before interest, tax, depreciation and amortization (EBITDA) for the three months to March 31 rose 5 percent to $669 million but came in well below the $852 million forecast by analysts in a Reuters poll.
Chief Executive Soren Skou called the result "unsatisfactory" but said he still expected EBITDA for the year at $4 billion-$5 billion.
Maersk shares fell almost 12 percent after the results to near 18-month lows, although quarterly revenue at $9.3 billion topped analysts' forecasts of $8.8 billion.
By 1241 GMT the shares were down 8.8 percent at 9,262 Danish crowns.
Analysts at Jefferies said disappointment stemmed in part from "relatively sluggish underlying volume growth" of 2.2 percent, short of an expected increase of 3-4 percent.
Container freight rates rose 7 percent, but the cost of shipping a container increased 12 percent, partly as a result of higher oil prices, Skou said.
Skou in previous quarters played down the risk of a global trade war hurting the group's business but on Thursday noted "increased uncertainties due to geopolitical risks and trade tensions."
"We have to admit that the Americans have taken a number of initiatives recently that have caught us by surprise," Skou told Reuters in an interview.
"The (trade) situation has become more intense," he said, adding it would hurt Maersk's business if trade talks between the United States and China ended in failure.
"The whole situation regarding Iran, which is pushing oil prices up, is certainly also not good for our container business," Skou said.
He added that Maersk was winding down its business in Iran following new U.S. sanctions: "I don't know the timing details exactly, but I am certain that we're also going to shut down (in Iran)."
After a slump in shipping and oil, Maersk is restructuring and divesting its energy businesses - including oil exploration, oil tankers and supply services - to focus on shipping, ports and logistics.
Skou said he would implement short-term initiatives to improve profitability and lower unit costs, which would include keeping fleet capacity unchanged in the next 18 months and no orders for new ships for at least 12 months.
He said he expected the global fleet supply balance to improve significantly in the second half of the year and in 2019.
Rival German container shipping line Hapag-Lloyd reported higher first-quarter profits on Monday.
Maersk said it still aimed to spin off its oil drilling and oil supply services units before the end of the year.
Reuters reported last week that the company is likely to shelve plans to list the offshore drilling division because of weak market conditions, and extend the timeline to divest the unit beyond its initial target of end-2018.
Before Thursday's results, Maersk shares had already fallen 29 percent from a July 2017 peak when optimism about freight rates and a turnaround in global container shipping began to fade.
(Reporting by Jacob Gronholt-Pedersen; Additional reporting by Stine Jacobsen; Editing by Jason Neely and Susan Fenton)