Sydney man denies sex acts near school

A Sydney man has denied sex acts with a woman in a park as children walked past on their way to a nearby school.

Luke Richard William Thomas, 39, pleaded not guilty to four charges - including behaving in an offensive manner near a public school - when he appeared briefly at Newtown Local Court on Monday.

The Manly man was arrested a week ago along with a 31-year-old woman - who will face court in March - after police received reports the couple was performing "a sexual act" in Weekley Park in Stanmore.

Police allege the incident occurred at 8.30am about 100 metres from a primary school as children were on their way to morning classes.

The 39-year-old was also charged with wilful and obscene exposure as well as two counts of possessing a prohibited drug after allegedly being caught with 0.3 grams of methamphetamine and 0.6 grams of cannabis.

He entered not guilty pleas to all charges on Monday and is scheduled to appear in court again on April 6.