Another blow for Prime Minister as support drops

Malcolm Turnbull will return from his Asia trip to a drop in the polls, not only for his party but also for his own approval as prime minister.

Prime Minister Malcolm Turnbull suffers another drop in the opinion polls. Source: AAP

Malcolm Turnbull has suffered a drop in the polls, with support for his government and approval of him as prime minister slipping.

Labor increased its two-party preferred lead for the fourth consecutive Newspoll to 55 per cent of surveyed voters against the coalition's 45 per cent, The Australian reported on Sunday night.

The prime minister is on a trip to Asia to attend several regional meetings, but the ongoing citizenship crisis within parliament has overshadowed the high-powered talks.

Opposition Leader Bill Shorten is closing in as the preferred prime minister, with Mr Turnbull suffering a five-point dip to an approval rating of 36 per cent.

Mr Shorten's support as preferred prime minister rose from 33 to 34 per cent.

The coalition's primary vote fell by one point from 35 to 34 per cent, while Labor's primary vote rose from 37 to 38 per cent.

One Nation increased its primary vote from nine to 10 per cent, while the Greens slipped one point to nine per cent.