SEOUL, July 28 (Reuters) - South Korea on Wednesday (Jul 28) reported 1,896 new COVID-19 cases for Tuesday, its highest-ever daily increase, as the country struggles to subdue a fourth wave of outbreaks fanned by the more contagious Delta variant of the coronavirus.

The daily tally broke a previous record set on Jul 22 as infections are spreading beyond the capital Seoul and its neighbouring regions where the toughest social distancing rules are in place.

There were 1,823 domestically transmitted cases on Tuesday and 33.5 per cent, or 611, of the were from areas outside the capital regions, according to the Korea Disease Control and Prevention Agency (KDCA).

This is the first time the number of cases outside the Seoul metropolitan region has exceeded the 600 mark since the first COVID-19 wave emerged from a church in the southeastern city of Daegu.

Tighter social distancing curbs took effect across most of the country on Tuesday and will last for two weeks. Those areas will be under Level 3 curbs on a four-level scale, which will mean a 10pm dining curfew and ban on gatherings of more than four people.

The tighter curbs were enacted to prevent the further spread of the coronavirus during South Korea's peak summer holiday season.

The great Seoul area region remains under Level 4 curbs that include a ban on gatherings of more than two people after 6pm.