BRUSSELS (Reuters) - The number of migrants entering the European Union by irregualr routes dropped overall by 38% in 2024, reaching the lowest level since 2021, the EU border agency Frontex said on Tuesday.

However, the number of people crossing from the EU's borders with Belarus and Russia jumped 192% to 17,000, Frontex said.

Significant numbers of migrants or asylum-seekers also came from Syria, Afghanistan, Egypt and African countries even as routes into the bloc shifted.

Irregular migration has become a key issue in European politics with many far-right and populist parties campaigning in recent and upcoming elections, including in Germany next month, on promises of getting tough on migration.

Frontex said the drop to just over 239,000 irregular border crossings last year was thanks to intensified EU and partner cooperation against smuggling networks. It was the lowest level since 2021 when migration was still affected by the COVID pandemic.

The overall reduction in irregular migration was mainly driven by a 59% plunge in arrivals via the Central Mediterranean route due to fewer departures from Tunisia and Libya and a 78% fall on the Western Balkan route thanks to strong efforts by countries in the region to stem the flow, Frontex said.

But there were 14% more cases, reaching 69,400, of irregular border crossing attempts on the Eastern Mediterranean route driven by new corridors from eastern Libya, with migrants predominantly from Syria, Afghanistan, and Egypt.

There was also an 18% rise in the number of migrants taking the Western African route to reach the Canary Islands with arrivals reaching almost 47,000 last year, fuelled by departures from Mauritania.

"While 2024 saw a significant reduction in irregular border crossings, it also highlighted emerging risks and shifting dynamics," Frontex head Hans Leijtens said.

(Reporting by Jan Strupczewski; Editing by Angus MacSwan)