The Pentagon said the order, authorized by the State Department, was for 79 Javelin missile launchers and 189 missiles worth $100 million.

Poland's conservative government has stepped up its efforts in Washington, which it regards as its most reliable ally, to reinforce the presence of US troops on its soil.

Polish President Andrzej Duda signed an agreement in January to buy 32 F-35 stealth fighters, in a deal worth $4.6 billion.

Warsaw also bought US-made HIMARS mobile rocket launchers and Patriot anti-missile systems, to build up its air defenses.

Meanwhile the United States has committed to increase the US military presence in Poland to 4,500 troops.

The sale to Ukraine of Javelin anti-tank missiles, which Kiev needed to defend against Russian-backed rebels, was the subject of an infamous telephone conversation last July between Trump and his Ukrainian counterpart Volodymyr Zelensky.

A White House summary of the conversation showed that when the newly elected Zelensky raised the missiles, Trump asked for a "favor" -- that Ukraine announce a corruption investigation into his political rival, Joe Biden, and his son.

The exchange triggered a whistleblower complaint that led to a congressional investigation and the president's impeachment for abuse of power by the House of Representatives.

Trump was acquitted in the Republican-controlled Senate after it voted against hearing from witnesses who could have testified against the president.