PADERBORN, Germany (Reuters) - German Chancellor Angela Merkel said on Saturday that Germany needed to make a national effort to deport migrants who do not have the right to stay in the country.

After an influx of almost 900,000 migrants last year, some Germans fear their country is being overrun by foreigners. Merkel has attracted criticism for her migrant policy and her conservatives have lost some support to the anti-immigrant Alternative for Germany (AfD).

In the past, when smaller numbers of asylum seekers arrived, those who were not granted the right to stay were not deported rigorously enough and that needs to change now, given the high number of refugees and migrants, Merkel said.

"We need a national push to deport those who are rejected. That's indisputable and we're working hard on that at the moment," Merkel told a conference of the youth wing of her conservatives in Paderborn.

She added that this would include boosting staff numbers at immigration authorities at the municipal level.

Deporting those migrants was only one element of Germany's refugee policy, Merkel said, adding that the integration of those who are granted protection must be expedited.

The causes of migration also needed to be tackled, she said.

(Reporting by Reuters TV; Writing by Michelle Martin; Editing by Andrew Bolton)