Rolls of barbed wire were being laid out in one section of the border near the spa town of Druskininkai, the Lithuanian government announced on Wednesday.

Preliminary work was also underway in other sections, it added.

After the installation of the barrier, an approximately four-metre-high fence reinforced with spiral barbed wire is to be erected as a second deterrent towards the end of the year.

Construction is scheduled for completion in 2022 and will cost up to 152 million euros ($A246 million).

In neighbouring Latvia, work is also underway to build a fence along the country's border with Belarus.

As a quick fix, more than 37 kilometres of barbed wire rolls are to be laid out at various sections of the border.

According to a report by Latvian radio, 1.7km have been covered so far.

Officials in Vilnius and Riga accuse Belarus of assisting refugees from war zones to reach the EU's external border and in so doing, create a migration crisis.

Belarus President Alexander Lukashenko warned the EU at the end of May that his country would no longer prevent migrants from travelling on to the EU, in retaliation for tightened sanctions against his government.

Lithuania, Latvia and Poland alike are all now struggling with an influx of migrants from the Middle East across their borders.

All three countries have now declared a state of emergency on their border.

Australian Associated Press