* Dollar index on track for 2.5% jump in June

* Middle East tensions, U.S. jobs data in focus

* ECB forum eyed for policy signals

By Jiaxing Li

HONG KONG, June 29 (Reuters) - The U.S. dollar was on the

defensive on Monday but remained on track for its biggest

monthly gain in nearly a year, due to tension in the Gulf and

ahead of jobs data that could shape the Federal Reserve's rate

path.

The U.S. and Iran traded fresh barbs over the weekend before

they agreed to stop tit-for-tat attacks and meet in Qatar on

Tuesday, leaving investors nervous about a fragile ceasefire.

Oil prices rose on Monday following strikes that again

slowed energy shipping in the Strait of Hormuz, supporting

safe-haven demand for the greenback.

The euro was flat at $1.1387 after hitting a 13-month

low against the dollar last week, and was on track for a 2.3%

monthly decline. Sterling traded 0.1% lower at $1.3198

and was down 2% for the month.

The risk-sensitive Australian dollar fetched

$0.6885, down 0.1% in early trade and heading for a 4.1% monthly

decline. The New Zealand dollar was little changed at

$0.5635, down 5.9% for the month.

The Japanese yen last traded at 161.75, continuing to

languish near a 40-year low.

The dollar index, which measures the greenback

against a basket of currencies including the yen and the euro,

was a shade higher at 101.36.

It is now on track for a 2.5% gain for June, which marks the

biggest monthly advance since July last year.

The conflict with Iran has continued to stoke inflation

pressures, while a surprisingly hawkish debut from Kevin Warsh

as Federal Reserve chair earlier in the month has reversed

market expectations for U.S. rate cuts this year.

Meanwhile, a tech-led global equity selloff is also driving

flows into the dollar as investors seek shelter.

Investors are now watching U.S. non-farm payroll

and unemployment rates due this week,

which could offer fresh clues on the strength of the labour

market and the outlook for Fed policy.

"We expect the USD to grind higher in coming weeks because

of the 'US exceptionalism' narrative," Joseph Capurso, head of

foreign exchange at Commonwealth Bank of Australia, said in a

note.

A strong and improving labour market is a recipe for higher

U.S. interest rates and the dollar, he said.

The European Central Bank's annual forum this week is also

under close watch as investors continue to monitor evolving

central bank policies amid lower oil prices and stock market

volatility.

ECB President Christine Lagarde opens the forum on Monday,

followed by a key policy panel on Wednesday featuring Fed Chair

Warsh, with markets looking for a clearer read on the new Fed

chief.