European foreign ministers, meeting on Monday to discuss aid to Ukraine, pressed Berlin to let countries send German-made Leopard tanks, after Germany appeared to open the door to such shipments by allies.

Western countries failed to reach agreement on sending Ukraine heavy battle tanks when they pledged billions of dollars worth of support last week at a U.S. air base in Germany.

Germany's Leopard tanks, fielded by armies across Europe, are widely seen as the best fit for Ukraine, but Berlin must authorise their sale and has yet to do so.

German Foreign Minister Annalena Baerbock said on Sunday that Berlin would not stand in the way if Poland wanted to send the tanks.

Arriving at the meeting in Brussels on Monday, she declined to elaborate on those comments in detail or say if she had been speaking for the whole government, but said it was important to "do everything we can to defend Ukraine".

Chancellor Olaf Scholz's centre-left Social Democrat party argues the West should avoid sudden moves that might escalate the war. But a number of allies reject that position, saying Russia is already fully committed to its assault on Ukraine.

"At this point there are no good arguments why battle tanks cannot be provided," Latvian Foreign Minister Edgars Rinkevics said. "The argument of escalation does not work, because Russia continues escalating."

Lithuanian Foreign Minister Gabrielius Landsbergis said the tanks should not be held up one more day, while Estonian Foreign Minister Urmas Reinsalu said Germany, as an "engine of Europe", had particular responsibility to help Ukraine. Luxembourg's Foreign Minister Jean Asselborn said Russia could win the war if Europeans "don't help Ukraine with what they need now".

The EU is considering sending a new tranche of 500 million euros worth of military aid to Kyiv. EU foreign policy chief Josep Borrell said he hoped member states would approve it on Monday, "but I don't know". French Foreign Minister Catherine Colonna said she was confident the package would be approved.

Polish media have reported that Hungary was holding up that package. The Hungarian foreign ministry and government spokesman did not respond to requests for comment on those reports.

The ministers will discuss a 10th package of sanctions to take effect next month against Russia, diplomatic sources have told Reuters, though no decisions are expected on Monday. The ministers will also talk about using Russian assets frozen in Europe under sanctions to help rebuild Ukraine.

Separately, the foreign ministers are due to add more names to an Iran sanctions list over human rights abuses.

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