ISLAMABAD (Reuters) - Pakistan is cracking down on portly policemen after only a quarter of the 19,000 officers in the Punjab province passed a fitness test.

Policemen in the South Asian nation are widely seen as corrupt and ineffective. Now their weight is coming under the spotlight as well.

The plump police, responsible for safeguarding the most populous province, were warned in letters to trim their waist-lines to the regulation 38 inches by the end of the month, local newspapers said on Friday.

Those who fail may be removed from field duties, The News reported.

This week local television channels have been repeatedly screening footage of overweight officers. They were shown snoozing in chairs, talking on phones and standing belly to belly, buckles straining.

The coverage made Punjab's Inspector General of Police Habib ur-Rehman even more determined to get his officers fit to fight crime, said a policeman from headquarters in Lahore.

The News reported that several policemen objected to the tests because senior officers had been exempted, and the men conducting them were overweight themselves.

Official police spokesmen were not available for comment, and it was unclear whether the problem affected other Pakistani provinces to the same extent.

Pakistan is fighting the Taliban in the northwest of the country, and criminal gangs in its major port city of Karachi.