PRAGUE (Reuters) - The Czech government has proposed that three central European states send hundreds of troops and police to help protect Hungary's borders against a migrant influx into Europe's Schengen passport-free travel zone, officials said on Friday.

The central Europeans have stressed the need to secure the European Union's outer borders as the basis of any response to the inflow of hundreds of thousands of refugees this year. Hungary's position is seen as pivotal as it forms the external boundary of the EU's Schengen passport-free travel zone.

"Our government is prepared to help Hungary with protection of the Schengen border. We are proposing joint V4 action,"

Czech Prime Minister Bohuslav Sobotka said on his Twitter page, referring to the Visegrad 4 group that compromises his country, Slovakia, Poland and Hungary.

Sobotka said their interior ministers would meet on Oct. 8 to tackle the idea.

Czech news agency CTK quoted Interior Minister Milan Chovanec as saying the plans could include sending hundreds of Czech, Polish and Slovak soldiers and police officers to help patrol Hungary's southern border for several months.

Hungary has drawn criticism from larger western EU countries and rights groups for measures it has taken to keep out migrants. It has built a high border fence facing non-EU member Serbia to the south and is racing to complete another one along its frontier with Croatia, an EU member but outside Schengen.

The Visegrad 4 have been in the spotlight over their strong resistance to mandatory national quotas to share out 120,000 asylum seekers among the EU's 28 member states, approved by a majority vote of the bloc's interior ministers last month.

Poland endorsed the measure but the Czechs, Slovaks and Hungarians continue to oppose quotas, saying it is better to focus on finding a solution to Syria's war, helping neighboring countries and protecting external EU borders.

Hungarian Prime Minister Viktor Orban has said the influx of refugees into Europe threatens to undermine the continent's Christian roots and that governments must control their borders before they can decide how many asylum seekers to take.

Hungary has been the most affected in central Europe by the migration wave, with 280,000 people entering its territory so far this year, although nearly all have sought just to pass on through to wealthier countries of the western EU. The other Visegrad nations have seen only a fraction of those numbers.

(Reporting by Jason Hovet and Petra Vodstrcilova; Editing by Mark Heinrich)