Poland does not rule out sending troops to Ukraine

"We should not exclude any option. Let Putin be guessing as to what we will do," Sikorski said when asked whether he would send Polish troops to Ukraine.

Sikorski said he has gone to Ukraine with his family in the past to deliver humanitarian aid. 

But a spokesperson for Poland's Defence Ministry, Janusz Sejmej, told Polish media on Tuesday he had "no knowledge of that" when asked about a report in Germany's Der Spiegel magazine suggesting Poland might send troops to Ukraine. 

The idea of sending foreign soldiers to Ukraine, which is battling Russian military aggression, was floated earlier this year in France, but no country, including Poland, has publicly embraced it.

Poland supports neighbouring Ukraine politically and by providing military equipment and humanitarian aid.