The Australian share market has retreated from the record highs set last week, ending its seven-day winning streak on the eve of a Reserve Bank meeting on interest rates.
The benchmark S&P/ASX200 index on Monday finished down 56.6 points, or 0.69 per cent, to 8,152.9, while the broader All Ordinaries dipped 53 points, or 0.63 per cent, to 8,384.2.
It was a rough day for supermarkets after the competition regulator announced legal action against Coles and Woolworths.
But uranium developers posted strong gains after a US utility announced plans to re-activate a notorious nuclear reactor to power artificial intelligence facilities.
Overall eight of the ASX's 11 sectors finished lower, with energy, technology and utilities higher.
The consumer staples sector was the biggest mover, dropping 2.8 per cent as Woolworths fell 3.4 per cent to a six-week low of $33.79 and Coles retreated 3.3 per cent to a two-week low of $18.59 on the legal claims.
Woolworths said it would engage with the Australian Competition and Consumer Commission about the allegations it had mislead consumers about its discounting practices, while Coles said it would defend the proceedings.
Other retailers also fell, with bottle shop owner Endeavour Group, Rebel owner Super Retail Group and Harvey Norman all dropping 2.2 per cent, while JB Hi-Fi dipped 2.0 per cent and Kmart owner Wesfarmers subtracted 1.7 per cent.
On the flip side, a trio of uranium developers were three of the four best performers in the ASX200 on Monday after it was announced the shuttered Three Mile Island nuclear plant in the US would be reactivated to provide energy for Microsoft's burgeoning AI operations.
Boss Energy grew 8.2 per cent to a nearly one-month high of $2.90, Deep Yellow climbed 5.1 per cent to a two-month high of $1.23 and Paladin Energy added 4.7 per cent to a three-week high of $9.86.
Elsewhere, Helius gained 7.5 per cent to a one-week high of $1.73 after the pathology chain announced plans to sell its diagnostic imaging business to Hong Kong-based private equity firm Affinity Equity Partners for $965 million.
"The sale will provide Healius with both the resources and time to continue to improve our pathology operations and the scope to return cash to shareholders," Helius chief executive Paul Anderson said.
In the heavyweight mining sector, BHP dropped 1.3 per cent to $39.81 and Rio Tinto slid 0.6 per cent to $112.34, while Fortescue added 0.3 per cent to $17.69.
The big four banks finished mixed, with CBA retreating 1.5 per cent to $142.39 and ANZ dipping 0.6 per cent to $31.70. NAB and Westpac both edged 0.1 per cent higher, at $39.70 and $33.61 respectively.
In the tech sector, Appen rocketed 18.8 per cent to a one-year high of $2.09, shares the AI dataset company having more doubled this month after reaching a nadir of 27c in January.
Back in the consumer discretionary sector, a new company with a familiar name made its debut on the bourse on Monday.
Shares in Webjet Group, trading under the ticker WJL, finished at 80c.
The company is a spinoff of the company formerly known as Webjet Limited, which has renamed itself WEB Travel Group, a business-to-business platform serving the hotel industry.
WEB's shares finished down 10.7 per cent to $7.35, reflecting their loss of value from the spinoff.
The Australian dollar was buying 68.11 US cents, from 68.20 US cents at Friday's ASX close.
Looking forward, the Reserve Bank is expected to leave rates on hold on Tuesday.
ON THE ASX:
* The benchmark S&P/ASX200 index finished Monday down 56.6 points, or 0.69 per cent, at 8,152.9
* The All Ordinaries dropped 53 points, or 0.63 per cent, at 8,384.2.
CURRENCY SNAPSHOT:
One Australian dollar buys:
* 68.11 US cents, up from 68.20 US cents at Friday's ASX close
* 97.98 Japanese yen, from 97.52 Japanese yen
* 61.14 euro cents, from 61.00 euro cents
* 51.26 British pence, from 51.15 pence
* 109.20 NZ cents, from 109.11 NZ cents
