He made the statement at a joint press conference with his French counterpart, Jean-Noel Barrot, following the annual meeting of French ambassadors in Paris on Monday.
Sikorski said the two countries had convergent views and joint plans to influence the situation when it comes to the war in Ukraine.
"A peaceful solution must take into account Ukrainian and European security interests," he said.
He added that while fighting against Russian aggression, Ukraine has not yet asked for the involvement of foreign troops on its territory.
"We agree that without a sovereign Ukraine there will be no safe Europe, Ukraine can count on our support, and its future is in the EU," Sikorski said.
He added that both countries will jointly strive to expand the area of stability and prosperity by accelerating the enlargement of the bloc, "both to the east and south-east."
Sikorski also said that cooperation with the United States remains crucial to Europe's security and prosperity and that only strong transatlantic ties will allow Europe to effectively counteract growing threats.
He encouraged enhancing "Europe's strategic responsibility and its defence capabilities, Europe’s strategic responsibility and defence capabilities, not in opposition to the US, but in strategic harmony with Washington."
According to Sikorski, this will require "understanding and compromises on both sides of the Atlantic."
He also warned that "Soon, we may face strong pressure to negotiate with Moscow.
"But what kind of agreement could a sensible Europe agree to? Of course, not an ordinary agreement that would allow Moscow to regain its strength. Europe is much stronger than Russian leaders think. Russia is much weaker than many Europeans think," Sikorski argued.
He added that "Ukraine deserves peace, needs peace but it should be on fair terms, not capitulation."
Sikorski also said that work on a new Polish-French friendship and cooperation treaty would be finalised in the coming months and that it will "represent a significant stimulus" to bilateral relations. (PAP)
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