WASHINGTON, May 27 (Reuters) -

U.S. corporate bond issuance kicked off to a strong

post-Memorial Day holiday start with offerings from 10

companies, including U.S. defense supplier Northrop Grumman ( NOC )

, automaker General Motors ( GM ) and insurer

Northwestern Mutual, on Tuesday.

The investment-grade bond spread, or the premium companies

paid over U.S. Treasuries, was just one basis point wider at 93

bps on Friday while the spread for junk bonds was 8 bps and last

stood at 340 bps, the ICE BofA Corporate Index

showed.

Spreads have since narrowed slightly as investors digested a

delay in U.S. tariffs on the European Union after President

Donald Trump held a weekend call with EU head Ursula von der

Leyen, said Dan Krieter, director of fixed income strategy at

BMO Capital Markets.

"That will likely translate to a fast start to this week's

primary market slate," Krieter wrote in a Tuesday morning note.

Syndicate desks project about $25 billion in

investment-grade bond supply this week, higher than the $20

billion average for the week following Memorial Day in the years

since 2016 excluding 2020, he added.

Investment-grade supply for May so far totals just under

$135 billion, according to Krieter. Meanwhile, junk bond

issuance totals $28.9 billion, the most for a month since

September 2024, according to JPMorgan research.

Global capital markets have been rattled by sharp bond

selloffs in recent weeks, as U.S. President Trump's erratic

tariff policy shifts have heightened concerns about the U.S.

Treasury's world standing.

This has lifted corporate bond yields, which have

contributed to relatively tight spreads, BofA credit strategist

Yuri Seliger wrote in a Friday note.

"Higher yields should be good for IG spreads, offsetting

some of the negative impact of the tariff headlines."

But yields on U.S. Treasuries and the yen slumped on Tuesday

following a Reuters report that the Japanese government would

consider issuing fewer longer-dated bonds.