Fitted with a 500lb high explosive blast warhead, the system is carried by 600 Nato warships and 180 submarines around the world.
The 15ft missiles are accurate to a range of 80 miles.
Harpoon missile can be put on trucks alongside a relatively simple command-and-control apparatus.
Because they are easy to move, they make the perfect fit for the Ukrainian military.
While the Harpoon missiles are older technology, they’re not currently in use by the Russian military.
And giving Ukraine access to these missiles means the US and its allies wont have to send more secretive weaponry, with concerns they might fall into the hands of Russia.
Up to 300 ships have been stopped by Russian forces from departing the Black Sea, leaving one of the key global trade routes for grain virtually blocked.
The fertile region is known as “the world’s breadbasket.”
British newspaper The Guardian reported that several other ships have been struck since the invasion began on February 24, including from Bangladesh and Estonia, which killed one person.
Russia blames the stoppage on the high risk of mines, which it said had been laid by the Ukrainian Navy.