Antanas Merkys (pronunciationⓘ; 1 February 1887 – 5 March 1955) was the last Prime Minister of independent Lithuania, serving from November 1939 to June 1940.

Merkys suggested accepting the ultimatum and offered to resign as prime minister, but he temporarily remained in office.

The following morning, the cabinet resolved that Smetona had effectively resigned by leaving the country, and confirmed Merkys as president.

On 17 June 1940 Merkys acceded to more Soviet demands—a) dispatch police to arrest Skučas and Povilaitis near the Lithuanian border[4] and b) appointing Justas Paleckis as the new prime minister.

Since Lithuania regained independence from the Soviet Union, it has maintained that Merkys' takeover of the presidency was illegal and unconstitutional, since Smetona never formally resigned.

Therefore, Lithuania contended that it did not need to follow the secession process outlined in the Soviet Constitution, since it was reasserting an independence that still existed under international law.

Subsequently, his grave could not be located, but a symbolic cenotaph dedicated to Merkys' memory is in the Petrašiūnai Cemetery in Kaunas.