Speaking at a news conference with his Ukrainian counterpart Denys Shmygal, Morawiecki said: "Today we stand side by side with the Ukrainian state to help and support the defense of the threatened Russian neighbor."
He added: "We express our solidarity in words and deeds. Poland is ready to provide support on gas, defense, economic and humanitarian issues."
Morawiecki announced that Poland would send tens of thousands of rounds of artillery ammunition, light mortars, man-portable air-defence systems and surveillance drones to its ex-Soviet neighbour to help it defend itself against a possible Russian move.
His statement came after a national security official in Warsaw said a day earlier that Poland would provide Kyiv with "defensive ammunition" amid fears of a new Russian attack on Ukraine.
Morawiecki told Tuesday's news conference in the Ukrainian capital: "This is the moment when all Europe and the entire Western world must unite for the sovereignty, independence and territorial integrity of Ukraine."
"Our part of Europe does not experience earthquakes or volcano eruptions, but living in such close proximity to Russia, we have a sense of living at the foot of a volcano," Morawiecki also told reporters in Kyiv.
'Berlin loading Putin's pistol' through Nord Stream 2
He called on Germany not to start the controversial Nord Stream 2 gas pipeline from Russia, saying the project posed serious security risks to Europe and warning that it could be used as a weapon by Russian President Vladimir Putin.
"Through launching this pipeline, Berlin is loading Putin's pistol, which he can then use to blackmail the whole of Europe," Morawiecki said.
Polish gas giant PGNiG said on Tuesday it had purchased a cargo of US liquefied natural gas (LNG) that would be sent to Ukraine by the end of March, Poland's PAP news agency reported.
An LNG carrier from the United States is expected to arrive in Poland later this month. After its arrival, the LNG will be re-gasified and sent to Ukraine via the Polish gas transmission system, the Polish state news agency reported.
"Thanks to investments in gas infrastructure … we can strengthen the energy security of the region by ensuring access to various sources of natural gas for our customers," PGNiG CEO Paweł Majewski was quoted as saying in a statement.
Warsaw, London, Kyiv team up to boost security: Ukrainian PM
Meanwhile, Ukraine's Shmygal told reporters in Kyiv on Tuesday that Poland, Britain and Ukraine were preparing a trilateral pact to strengthen regional security, the Reuters news agency reported.
He said that Poland and Britain had offered security aid to Ukraine in its standoff with Moscow after Russia massed tens of thousands of troops near Ukraine's borders in recent weeks.
"I hope that in the near future we will be able to officially launch a new regional format of cooperation Ukraine-Poland-UK, in the context of ongoing Russian aggression, we should sign a trilateral document on cooperation to strengthen regional security," Shmygal said, as quoted by Reuters.
British Prime Minister Boris Johnson was due to arrive in Kyiv later in the day.
'Not only diplomatic gestures'
While in Kyiv on Tuesday, Poland's Morawiecki was also scheduled to hold talks with Ukrainian President Volodymyr Zelensky.
Morawiecki said ahead of his Kyiv trip that "in the face of the threat to the sovereignty of Ukraine, not only diplomatic gestures are needed, but also real help."
He added that "the most important thing at the moment is to support our neighbour and help it defend its independence and territorial integrity."
Polish government spokesman Piotr Müller said earlier in a tweet that "Poland supports Ukraine in its efforts to prevent Russian aggression" and that it "will do everything possible to maintain peace in Europe."
'Comprehensive support' for Ukraine
That announcement came after Polish lawmakers last week adopted a resolution to support Ukraine amid the threat of a new Russian invasion.
The resolution, which was approved by the Polish lower house on Thursday, called on NATO and the European Union to offer more “comprehensive support” to Ukraine amid intensifying tensions with Moscow.
It condemned Russia for undermining peace in Europe and breaking international law.
Earlier last week, Polish President Andrzej Duda told reporters that NATO was united in its support of Ukraine amid a standoff with Moscow.
He was speaking after a video call last Monday with US President Joe Biden and the leaders of France, Germany, Italy, Britain and the European Union.
Ukraine 'can count on Poland's support': president
Duda last month met with Ukraine's Zelensky in the southern Polish resort town of Wisła to discuss regional security and the risk of further Russian aggression against Kyiv.
He declared after those talks that Ukraine "can count on Poland's support" in the event of a Russian attack.
Polish Deputy Foreign Minister Szymon Szynkowski vel Sęk has said in a media interview that Ukraine "has a right to choose its alliances" and that "there is no return" to the kind of world order based on spheres of influence that existed in the Cold War days.
Russia's deployment of troops near Ukraine has raised fears in the West that Moscow, which seized Ukraine's Crimea peninsula in 2014 and has since backed separatists fighting in eastern Ukraine, may be poised for a new attack, the Reuters news agency has reported.
Russia has denied plans for an assault but says it could take unspecified military action if its security demands are not met, according to Reuters.
Source: PAP, TVP Info, Reuters