Tanker stocks have cooled off after last week's rally amid declining rates and a sector-wide downgrade.

Many tanker owners saw gains last week, with the 10 covered by Jefferies' Randy Giveans, rising an average of 6%.

But on Tuesday, the Baltic Dirty Tanker Index fell 45 points to 653, continuing its five-day slide from 733 on 27 May as oil prices — which investors have appeared to tie to weaker tanker sentiment — rose 4% to $36.85 on the West Texas Intermediate benchmark and Brent crude 3.3% to $39.60.

International Seaways led the way, sliding nearly 8% to $21.39, after closing last week at $22.66 and trading as high as $23.67 on Monday.

The Lois Zabrocky-led company was followed by fellow crude tanker owners Teekay Tankers, Diamond S Shipping and DHT Holdings, which fell 5.7%, 4.4% and 2.5% respectively.

Teekay Tankers shares closed at $16.32, Diamond S at $10.32 and DHT at $5.90.

Product tanker owners, which saw the Baltic Clean Tanker Index slide 14 points to 546, also fell.

The owner of the world's largest product tanker fleet, Scorpio Tankers, slid 5.1% to $16.65, while Ardmore Shipping Corp fell 4.5% to $5.48.

The declines also came after Fearnleys Securities downgraded several leading owners, arguing the possibilities for improved rates have "gone for the summer".

International Seaways, Scorpio Tankers and Ardmore were among the companies downgraded to sell as it expects difficulties in the near term thanks to expected extensions of Opec+ supply cuts and destocking of the supplies built up when oil was cheap in the spring.

However, the bank does expect the medium term to be positive for tankers, with a low orderbook and oil production expected to ramp up in 2021.