Deputy lower-house Speaker Małgorzata Kidawa-Błońska has told reporters that MPs will hear from government officials about "the current situation on the border" before holding a debate on the migrant crisis.
The government's spokesman Piotr Müller told the state-run TV news channel TVP Info on Monday that a special parliamentary session was necessary. "Hopefully, we will see some cross-party solidarity," he said.
"We have an extraordinary situation on our hands, with another country disrupting the integrity of Poland's borders in an organised manner," Müller said.
He was speaking after hundreds of migrants escorted by Belarusian officials amassed in front of the border village of Kuźnica, in Poland's eastern Podlaskie province, in an attempt to storm the Polish frontier.
Müller added that "the situation on the Polish-Belarusian frontier is the most difficult since the migrant crisis began," and "unfortunately our analysis shows it is going to escalate."
'We are expecting provocations'
"We are expecting provocations," Müller told reporters, warning that "shots could be fired in the direction of our border," PAP reported.
'We will defend peace in Europe': PM
Polish Prime Minister Mateusz Morawiecki said in a Twitter post on Tuesday that "sealing the Polish border is our national interest. But today the stability and security of the entire EU is at stake."
He added: "This hybrid attack of Lukashenko’s regime is aimed at all of us. We will not be intimidated and will defend peace in Europe with our partners from NATO and EU."
As Poland's leaders held crisis meetings on Monday, Morawiecki said his government was focused on protecting the country's citizens and the European Union's external border amid an escalating migrant crisis manufactured by Belarus.
Polish border guards, police and soldiers on Monday thwarted several attempts by migrants to force their way into the country via Belarus, government officials said, as the border crisis escalated.
The United States on Monday voiced concern over "disturbing images and reports" from the Polish-Belarusian border, and condemned Belarus for "orchestrating" migrants flows to Europe.
NATO condemned the use of migrants by Belarus "as a hybrid tactic," Poland's PAP news agency reported.
Meanwhile, European Commission head Ursula von der Leyen called for EU member states to approve new sanctions against Belarus, which she said was responsible for a "hybrid attack" on the Polish border using migrants.
The European Union has accused Belarus of encouraging thousands of migrants from the Middle East and Africa to cross into EU countries via Belarus, as a form of hybrid warfare in revenge for Western sanctions on Minsk over human rights abuses, the Reuters news agency reported.
Poland and the Baltic states have accused Belarus's strongman leader Alexander Lukashenko of organising a wave of illegal migrants seeking to enter the bloc as part of what officials have called a "hybrid war."
The EU Commissioner for Home Affairs, Ylva Johansson, visited Poland in late September, agreeing with Warsaw’s arguments that “firm steps” were needed against Belarus, according to officials.
Poland's Prime Minister Mateusz Morawiecki said last month that his country enjoyed full support within the European Union as it worked to defend itself against a migrant influx and a "hybrid war" being waged by Belarus.
In late September, Polish lawmakers voted overwhelmingly to extend a state of emergency in parts of two regions along the country's eastern border with Belarus by two months amid a growing migrant surge.
The state of emergency gives authorities broader powers to monitor and control the movement of people on the Polish-Belarusian border, which is also the eastern border of the European Union.