Barclays raised its crude price forecasts for this year and next on Thursday, saying the market is "tightening" amid plunging output in Venezuela and the potential for further supply disruptions as the U.S. re-imposes sanctions on Iran.

The bank raised its 2018 Brent price forecast to $73 per barrel from $61.8, and 2019 price view to $70 a barrel from $60.

It also raised its price forecast for U.S. crude or, West Texas Intermediate (WTI) to $68.20 per barrel for this year from $57 earlier, and 2019 forecast to $65 per barrel from $55.

"The (oil) market is tightening and with the combination of rapidly falling Venezuela production and the potential impact of Iranian sanctions we now see it as appropriate to factor in at least some of the windfall profitability", Barclays analysts said in a note.

Oil prices hit $80 a barrel on Thursday for the first time since November 2014 on concerns Iranian exports could fall, reducing supply in an already tightening market.

Last week, U.S. President Donald Trump pulled the U.S. out of a 2015 international nuclear pact with Iran, and plans to re-impose U.S. economic sanctions on the country, casting further uncertainty over global oil supplies. 

Meanwhile, output in Venezuela, a major oil producer, has slumped due to an economic crisis, and on Monday, told the Organization of the Petroleum Exporting Countries its production in April dropped to a new long-term low of 1.505 million barrels per day. 

The investment bank also said oil markets may tighten further in both 2019/2020.

(Reporting by Karen Rodrigues and Koustav Samanta in Bengaluru; Editing by Elaine Hardcastle) ((K.Rodrigues@thomsonreuters.com; Within U.S. +1 651 848 5832, Outside U.S. +91 80 6749 9229; Reuters Messaging: K.Rodrigues.thomsonreuters.com@reuters.net))