The Australian and NZ dollars fell against their major counterparts in the Asian session on Monday, as worries over a new variant of Covid-19 spreading in Britain and uncertainty about a post-Brexit deal before the end of the year deteriorated risk sentiment.

The British government on Saturday imposed tighter restrictions on London and south-east England, warning that the new strain of the virus was "out of control".

European countries have imposed travel bans on the U.K., while other countries are expected to follow suit.

Virus cases continued to rise on Sydney in Australia, prompting other states and territories to prohibit travelers from the city.

Resurgence in virus outbreaks around the globe overshadowed news of U.S. lawmakers agreeing to the much-awaited aid package of around $900 billion.

The aussie depreciated to 5-day lows of 0.7556 against the greenback and 78.15 against the yen, off its early highs of 0.7606 and 78.64, respectively. The aussie is poised to find support around 0.73 against the greenback and 76.00 against the yen.

The aussie reversed from its early highs of 1.6075 against the euro and 0.9739 against the loonie and was trading at 1.6136 and 0.9704, respectively. The next key support for the aussie is seen around 1.65 against the euro and 0.96 against the loonie.

The aussie pulled back to 1.0660 against the kiwi, after touching 1.0700, which was its strongest level since November 9. If the aussie slides further, 1.045 is likely seen as its next support level.

Data from the Reserve Bank of New Zealand showed that New Zealand's credit card spending rose for the third month in a row in November.

Overall credit card spending rose 0.1 percent month-on-month in November, after a 1.5 percent increase in October.

The kiwi weakened to 5-day lows of 0.7084 against the greenback and 73.23 against the yen, down from its early highs of 0.7124 and 73.66, respectively. The kiwi is seen finding support around 0.68 against the greenback and 72.00 against the yen.

The kiwi edged down to 1.7212 against the euro, from a high of 1.7158 set at 6:00 pm ET. On the downside, 1.74 is likely seen as its next support level.

Looking ahead, Canada new housing price index for November is due in the New York session.

Eurozone flash consumer sentiment index for December is set for release at 10:00 am ET.