* Polish opposition lawmakers still occupy main hall of parliament
* Media protest against curbing their access to parliament
* Opposition says budget passed illegally
By Marcin Goclowski
WARSAW, Dec 19 (Reuters) - Polish opposition lawmakers who accuse the ruling PiS party of undermining democracy and the constitution occupied the main hall of parliament for a fourth day on Monday as efforts to defuse the country's biggest political standoff in years continued.
President Andrzej Duda will meet later with the speaker of parliament Marek Kuchcinski and Law and Justice (PiS) party chief Jaroslaw Kaczynski to discuss the situation. Duda, a PiS ally, held a meeting with opposition leaders on Sunday.
"Something wrong has happened to Polish democracy," the leader of the biggest opposition party, Civic Platform (PO), Grzegorz Schetyna told private radio station RMF FM, saying he was ready to meet with Kaczynski, who has no formal role in government but is seen as a strong influence on party policy.
Since coming to power in October 2015 the nationalist-minded, eurosceptic PiS has come under fire at home and abroad for what critics say are undemocratic moves designed to tighten its grip on power.
These include changes to the constitutional court that led the European Commission to say democracy and the rule of law were under threat in Poland and which Poles continued to protest against over the weekend. It has also moved to exert more control over state prosecutors and approved legislation that human rights groups said would curtail freedom of assembly.
The current political crisis began last week when the PiS announced plans to curb media access to parliament and escalated on Friday when a vote on the 2017 budget was moved outside parliament's main chamber, with the opposition and media excluded.
That prompted opposition parties to accuse PiS of violating the constitution and protests from the media. Demonstrators surrounded parliament and ruling party politicians had to ask the police for help to leave the building.
Internal affairs minister Mariusz Blaszczak was quoted as saying by state-run news agency PAP on Monday that those protests were intended "to block the state budget, to create a political crisis".
Street demonstrations continued at a low level on Monday, with more planned for later in the day.
PiS's plan would see all direct recording of parliamentary sessions banned from Jan. 1 except by five selected television stations, while the number of journalists allowed in the parliament building would be limited to two per media outlet.
The PiS has already tightened control over public news media and critics see the curbs as an extension of that.
A poll for daily Rzeczpospolita on Monday found 68 percent of Poles think curbing media access would limit their ability to know what parliament is doing.
Financial markets reacted calmly to the crisis on Monday. The zloty currency was little changed at 4.41 per euro, while the main stock market index WIG eased by 0.7 percent. (Reporting by Marcin Goclowski; Editing by Catherine Evans)