Israeli tanks and aircraft carried out new strikes on Hamas targets in Gaza overnight in response to the launch of so-called fire balloons across the border, the army said on Tuesday.

Israel has bombed the Hamas-ruled enclave almost daily since August 6, in response to the airborne incendiary devices and, less frequently, rockets launched across the border. "Fighter jets, tanks and aircraft struck military posts and an underground infrastructure belonging to the Hamas terror organisation in the southern Gaza Strip," the army said.

The flare-up comes after US Secretary of State Mike Pompeo visited Israel on Monday and as British Foreign Secretary Dominic Raab was due to hold talks in both Israel and the Palestinian Territories on Tuesday.

The fire balloons -- makeshift incendiary devices fitted to inflated balloons, condoms or plastic bags -- have sparked multiple blazes on farmland in southern Israel, causing significant damage to crops. They are widely seen as an attempt by Hamas to improve the terms of an informal truce under which Israel committed to ease its 13-year-old blockade in return for calm on the border.

But so far Israel's response has been to tighten the blockade. It has banned Gaza fishermen from going to sea and closed its goods crossing with the territory, prompting the closure of Gaza's sole power plant for want of fuel.

An Egyptian delegation has been shuttling between the two sides to try to broker a renewal of the truce, so far without result. Egypt has acted to calm repeated flare-ups in recent years to prevent any repetition of the three wars Israel and Hamas have fought since 2008.

The latest ceasefire, which has already been renewed several times, is bolstered by millions of dollars in financial aid from Qatar to Gaza. The truce provided for permits for Gazans to work in Israel and financing for Gaza development projects, both measures that would provide some economic relief in an impoverished territory where unemployment exceeds 50 percent.

According to a source close to Hamas, the movement wants the extension of an industrial zone in the east of Gaza, and the construction of a new power line. Hamas also wants the number of Israeli work permits issued to Gazans to be doubled to 10,000 once anti-coronavirus restrictions are lifted, the source said.

On Monday, the Hamas authorities announced a 48-hour curfew across the territory after four cases of the virus were confirmed in a Gaza Strip refugee camp.