Poland's Prime Minister Donald Tusk on Thursday hailed progress in talks with Ukraine on disputes over farm imports that have frayed ties between the neighbouring allies.

Poland has been a staunch supporter of Ukraine as it fights off a Russian invasion, but their relations have soured over the past months over economic disputes.

Polish farmers have blocked the border over complaints that Ukrainian food imports have undercut prices for their own produce.

"In the matter of agriculture, we have moved a step forward," Donald Tusk told reporters after hosting his Ukrainian counterpart Denys Shmygal.

"Today I can say that we have definitely made progress in lifting the blockade," said Shmygal.

"Our plan is being implemented. Not as fast as we would like, but we definitely have positive trends and dynamics," he added. 

Tusk said the allies were "close" to an agreement.

"We're looking for solutions and we're close to them...," he added. "This concerns the quantity of products that can flow to Poland."

The issue of the transit of Ukrainian goods through Poland was also discussed, he said.

Kyiv has repeatedly urged its EU neighbour to ease the cross-border traffic hold-ups, warning that delays triggered by the blockades could impede weapons deliveries to the country.

Ukraine has accepted limits on its exports proposed by the European Commission, said Shmygal, as well as setting up a system of export licences for wheat, corn, colza and sunflowers.

The two leaders also signed a joint declaration outlining directions for future talks.

Before the latest meeting, Polish government officials had sought to tone down expectations. They had warned that finding long-lasting solutions would take more time.

Ukraine's agricultural sector has been crippled by Russia's 2022 invasion, with many export routes through the Black Sea blocked and swaths of farmland rendered unusable by the conflict.

The two sides also discussed accusations by Polish truckers who say their Ukrainian counterparts are undercutting prices and working conditions.

In addition, Poland said it had proposed greater cooperation in the production and modernisation of helicopters, the manufacture of 125-mm shells, the delivery of air-defence systems, and tank maintenance.