Hungarian Defence Minister Csaba Hende resigned Monday, according to a government statement given to state news agency MTI, without giving a reason.

After the meeting, during which Hende gave an update on Hungary's migration crisis as well as progress on the building of a 4-metre fence on the border with Serbia, the 55-year-old gave notice of his resignation to Prime Minister Viktor Orban, who accepted, MTI said.

Around 167,000 migrants have entered Hungary illegally so far this year.

Hungary has in recent months joined Italy and Greece as a "frontline" state in Europe's migrant crisis, with 50,000 people trekking up the western Balkans and entering the country in August alone.

The right-wing government headed by Orban responded by instructing the army to erect a controversial razor-wire barrier along its 175-kilometre (110-mile) border with Serbia.

In addition the army is also building a four-metre high fence, due to be completed by October 31.

November was the original deadline for the fence's completion when the plan was announced July, but a month later Orban declared the border would be closed by August 31.

Hende had served as defence minister since Orban's government came into power in 2010, and will be replaced by Istvan Simicsko, 53, a current state secretary for sport.