British businessman and former Wananchi Group CEO Richard Alden was charged on Tuesday with having a firearm without a certificate.
Alden, 53, was to plead to the charge last week but the prosecution requested that the plea be deferred to today. He denied the charge.
The Briton is facing other charges of forging a firearm certificate and preparing a document without authority.
Milimani chief magistrate Daniel Ogembo ordered that he remain in custody until Wednesday when a bail hearing will take place.
Ogembo adjourned the ruling after the prosecution led by senior state counsel Eddie Kadebe opposed the bail application.
Alden was released last week on Sh2 million cash bail with two Kenyan sureties over the death of his girlfriend at his house in Karen, Nairobi.
He denied killing Grace Wangeci, 42, in his house on Windy Ridge Road in Karen, Nairobi, on June 4.
It had been reported that the woman accidentally shot herself while taking selfies with the firearm. But investigators ruled this out and charged Alden with murder.
The High Court had opposed his release on bail saying the reasons given were not compelling.
Alden was ordered to report to the OCS in Karen twice a week and surrender his passport pending the hearing of his case.
DPP Keriako Tobiko had opposed the bail application saying Alden is a foreigner with no fixed abode and a flight risk.
But Alden said he would comply with bail conditions, adding he is a father of three and has an ailing mother who depends on him.