Polish customs officers will decide by Monday whether to end a strike that has paralysed Poland's borders with its eastern neighbours, a trade union official said on Saturday, Reuters reported. "It has been agreed in talks with the (finance) ministry that we have until Monday to give our reply," the news agency PAP quoted Jacek Staniszewski of the federation of customs officers' unions as saying. The strike over pay began six days ago. The government has offered the officers a 500-zloty ($202) rise, far below their demand for nearly double their monthly salary to about 4,000 zlotys ($1,620). The proposal includes extending to the customs officers legal protection and other benefits enjoyed by members of other uniformed services. Hundreds of truck drivers have been stranded in rural border areas and some have threatened to blockade Warsaw and other cities in reprisal. Only trucks carrying livestock or perishable food have been allowed across the border, news reports said. Poland's eastern borders with Belarus, Ukraine and Russia became the European Union's eastern frontier in December when Poland and eight other eastern EU members joined the bloc's border-free Schengen zone. PAP said the Foreign Ministry of neighbouring Belarus had called on the European Union to "fulfil its commitment to the free flow of goods and people across the EU's external borders", which it said had become paralysed.